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1.
Clin Respir J ; 18(4): e13750, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38616354

ABSTRACT

BACKGROUND: Pulmonary mucinous adenocarcinoma is a special type of lung cancer. Its imaging manifestations are diverse, which brings challenges to clinical diagnosis. However, its formation mechanism is unclear. OBJECTIVE: The objective of this study is to analyse the relevant mechanisms of the formation of pulmonary mucinous adenocarcinoma by observing its different imaging and pathological manifestations. DATA AND METHODS: Retrospective analysis was conducted on imaging manifestations and pathological data of 103 patients with pulmonary mucinous adenocarcinoma confirmed intraoperatively or pathologically. RESULTS: Forty-three patients had pulmonary mucinous adenocarcinoma with a solitary nodule/mass, 41 patients with localized pneumonia and 19 patients with diffuse pneumonia. Their CT manifestations included 'falling snowflake sign', ground-glass opacity close to the heart, vacuous signs/honeycombing and withered tree branches. Under the microscope, all the three types of pulmonary mucinous adenocarcinoma had visibly formed mucus lakes but were made of tumour cells with totally different shapes, which included the goblet-like shape (tall column-like shape) and quasi-circular shape. Tall column-shaped tumour cells were negative or weakly positive for thyroid transcription factor-1 (TTF-1) and strongly positive for ALK mutation, whereas quasi-circular tumour cells were positive for TTF-1 and less positive for ALK mutation. CONCLUSION: The different imaging manifestations of mucinous adenocarcinoma are possibly due to the different amounts or viscosity of mucus produced, and the mechanisms of its formation may include (1) tumour cells in different shapes have different abilities to produce mucus; (2) tumours in different stages produce different amounts or viscosity of mucus; and (3) the TTF-1 and ALK genes affect the production of mucus.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Pneumonia , Humans , Retrospective Studies , Lung Neoplasms/diagnostic imaging , Receptor Protein-Tyrosine Kinases
2.
BMC Cancer ; 24(1): 372, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38528507

ABSTRACT

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) recommended for the patients with subsolid nodule in early lung cancer stage is not routinely. The clinical value and impact in patients with EGFR mutation on survival outcomes is further needed to be elucidated to decide whether the application of EGFR-TKIs was appropriate in early lung adenocarcinoma (LUAD) stage appearing as subsolid nodules. MATERIALS AND METHODS: The inclusion of patients exhibiting clinical staging of IA-IIB subsolid nodules. Clinical information, computed tomography (CT) features before surgical resection and pathological characteristics including tertiary lymphoid structures of the tumors were recorded for further exploration of correlation with EGFR mutation and prognosis. RESULTS: Finally, 325 patients were enrolled into this study, with an average age of 56.8 ± 9.8 years. There are 173 patients (53.2%) harboring EGFR mutation. Logistic regression model analysis showed that female (OR = 1.944, p = 0.015), mix ground glass nodule (OR = 2.071, p = 0.003, bubble-like lucency (OR = 1.991, p = 0.003) were significant risk factors of EGFR mutations. Additionally, EGFR mutations were negatively correlated with TLS presence and density. Prognosis analysis showed that the presence of TLS was associated with better recurrence-free survival (RFS)(p = 0.03) while EGFR mutations were associated with worse RFS(p = 0.01). The RFS in patients with TLS was considerably excel those without TLS within EGFR wild type group(p = 0.018). Multivariate analyses confirmed that EGFR mutation was an independent prognostic predictor for RFS (HR = 3.205, p = 0.037). CONCLUSIONS: In early-phase LUADs, subsolid nodules with EGFR mutation had specific clinical and radiological signatures. EGFR mutation was associated with worse survival outcomes and negatively correlated with TLS, which might weaken the positive impact of TLS on prognosis. Highly attention should be paid to the use of EGFR-TKI for further treatment as agents in early LUAD patients who carrying EGFR mutation.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Tertiary Lymphoid Structures , Humans , Female , Middle Aged , Aged , Retrospective Studies , Adenocarcinoma of Lung/diagnostic imaging , Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/genetics , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Prognosis , Mutation , ErbB Receptors/genetics , ErbB Receptors/therapeutic use
3.
Small ; 20(2): e2304404, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37670529

ABSTRACT

Cyano-rich g-C3 N4 materials are widely used in various fields of photochemistry due to the very powerful electron-absorbing ability and electron storage function of cyano, as well as its advantages in improving light absorption, adjusting the energy band structure, increasing the polarization rate and electron density in the structure, active site concentration, and promoting oxygen activation ability. Notwithstanding, there is yet a huge knowledge break in the design, preparation, detection, application, and prospect of cyano-rich g-C3 N4 . Accordingly, an overall review is arranged to substantially comprehend the research progress and position of cyano-rich g-C3 N4 materials. An overall overview of the current research position in the synthesis, characterization (determination of their location and quantity), application, and reaction mechanism analysis of cyano-rich g-C3 N4 materials to provide a quantity of novel suggestions for cyano-modified carbon nitride materials' construction is provided. In view of the prevailing challenges and outlooks of cyano-rich g-C3 N4 materials, this paper will purify the growth direction of cyano-rich g-C3 N4 , to achieve a more in-depth exploration and broaden the applications of cyano-rich g-C3 N4 .

4.
Quant Imaging Med Surg ; 13(7): 4339-4349, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37456298

ABSTRACT

Background: Ciliated muconodular papillary tumor (CMPT) is a rare pulmonary tumor with papillary architecture. Most studies have focused on the clinicopathological features of CMPT, while computed tomography (CT) characteristics have rarely been systematically described. Methods: A cohort of 27 patients with surgically resected CMPT were identified. Clinical and demographic features were recorded. Preoperative CT images of the CMPTs and the corresponding histopathological basis were also retrospectively analyzed. Results: All of the tumors appeared as solitary nodules. Pure ground glass, part-solid nodules and solid nodules were detected in 2/27 (7.4%), 17/27 (63.0%), and 8/27 (29.6%) patients, respectively. Twenty-one tumors (77.8%) were located in the lower lobe. The average tumor size was 1.21±0.74 (range, 0.44-3.46) cm. Eighteen (66.7%) of the 27 patients had tumors with well-defined margins and lobulated contours. Fifteen patients (55.6%) had air bronchograms in the tumor, and 19 patients (70.4%) had air-containing space. There were two patients whose tumor size was enlarged and accompanied by an increase in solid components, and one patient simply had an increase in tumor size at the preoperative follow-up duration. Notably, one patient with solid tumor components was finally diagnosed with CMPT accompanied by adenocarcinoma. Conclusions: CMPTs of the lung mostly manifest as solitary, lobulated, well-defined tumors with air-containing spaces on CT and often occur in the periphery of the pulmonary lower lobe. When CT findings meet these criteria, the possibility of CMPT should be considered. Additionally, CMPT can coexist with adenocarcinoma. Further investigation will contribute significantly to the biological properties of CMPT and its relationship to the potential for malignant transformation.

5.
BMC Cancer ; 23(1): 203, 2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36869304

ABSTRACT

BACKGROUND: With the application of immune checkpoint inhibitors (ICIs) in cancer treatment, more and more attention has been paid to checkpoint inhibitor-related pneumonitis (CIP), which requires a better understanding of its clinical characteristics and therapeutic effects. METHODS: The clinical and imaging data of 704 patients with non-small cell lung cancer (NSCLC) who received immunotherapy were analyzed retrospectively; the clinical characteristics of CIP were summarized, and the therapeutic regimens and effects of the patients were summarized. RESULTS: 36 CIP patients were included in the research. The most common clinical symptoms were cough, shortness of breath and fever. The CT manifestations were summarized as follows: Organizing pneumonia (OP) in 14 cases (38.9%), nonspecific interstitial pneumonia (NSIP) in 14 cases (38.9%), hypersensitiviy pneumonitis(HP) in 2 cases (6.3%), diffuse alveolar damage in 1 case (3.1%) and atypical imaging manifestations in 5 cases (13.9%). 35 cases received glucocorticoid therapy, 6 patients were treated with gamma globulin and 1 patient was treated with tocilizumab. There were no deaths in CIP G1-2 patients and 7 deaths occured in CIP G3-4 patients. 4 patients were treated again with ICIs. CONCLUSION: We found that glucocorticoid 1-2 mg/kg was effective for most patients with moderate to severe CIP, and a few patients with hormone insensitivity needed early immunosuppressive therapy. A few patients can be rechallenged with ICIs, but CIP recurrence needs to be closely monitored.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Pneumonia , Humans , Glucocorticoids , Retrospective Studies
6.
Front Immunol ; 13: 984666, 2022.
Article in English | MEDLINE | ID: mdl-36275670

ABSTRACT

This study evaluated the efficacy of neoadjuvant immunochemotherapy (Io+Chemo) versus chemotherapy alone (Chemo) in resectable non-small cell lung cancer (NSCLC) in a real-world setting. The association of tumor immune microenvironment (TIME) with pathologic response to different neoadjuvant therapies was also explored.Stage I-III NSCLC patients who received Io+Chemo or Chemo alone followed by surgery were included in the study. Tumor tissues collected during surgery were subjected to TIME evaluation using multiplex immunohistochemistry to measure immune cell subsets, including T cells, B cells, NK cells, and macrophages. Fifty-five patients were included, including 24 treated with neoadjuvant Io+Chemo and 31 with Chemo alone. Io+Chemo induced significantly higher major pathologic response (MPR) (75.0% vs. 38.7%, P = 0.0133) and numerically better pathologic complete response (pCR) (33.3% vs. 12.9%, P = 0.1013) than Chemo. Compared with tumors with Chemo, tumors with Io+Chemo demonstrated a significantly higher ratio of M1 macrophage density in the tumor to that in the stroma (P = 0.0446), more abundant CD8+ cells in the stroma (P = 0.0335), and fewer PD-L1+CD68+ cells in both tumor and stroma. pCR/MPR patients displayed significantly higher density of CD3+, CD3+CD4+, CD20+, CD56 bright cell subsets and more tertiary lymphoid structures and significantly lower density of PD-L1+CD68+ and CD3+CD4+Foxp3+cells in the tumor or stroma. This study favored neoadjuvant Io+Chemo over Chemo and revealed the TIME features underlying the outperformance of Io+Chemo over Chemo.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Neoadjuvant Therapy , B7-H1 Antigen , Tumor Microenvironment , Forkhead Transcription Factors
7.
BMC Pulm Med ; 22(1): 369, 2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36171571

ABSTRACT

BACKGROUND: Part-solid nodules (PSNs) have gradually shifted to defining special clinical subtypes. Commonly, the solid portions of PSNs show various radiological morphologies, of which the corresponding pathological basis and prognosis are unclear. We conducted a radiological-pathological evaluation to determine the histopathologic basis of different consolidation radiographic morphologies related to prognosis. MATERIALS AND METHODS: A cohort of 275 patients with a surgical pathological diagnosis of lung adenocarcinoma were enrolled. Preoperative computed tomography (CT) images of the PSNs were recorded and assessed. A panel of 103 patients with complete pathological specimens was selected to examine the radiological-pathological associations, and follow-up was performed to identify the prognosis. RESULTS: Of the 275 patients, punctate consolidation was observed radiologically in 43/275 (15.7%), stripe consolidation in 68/275 (24.7%), and irregular consolidation in 164/275 (59.6%) patients. The radiological morphology of the solid components was significantly associated with the histopathological subtypes (P < 0.001). Visual punctate solid components on CT correlated with tertiary lymphoid structures, stripe solid components on CT correlated with fibrotic scar, and irregular solid components on CT correlated with invasion. PSNs with regular consolidation had a better prognosis than those with irregular consolidation. CONCLUSION: Radiological morphology of solid components in PSNs can indicate the pathological basis and is valuable for prognosis. In particular, irregular solid components in PSNs usually indicate serious invasive growth, which should be taken with caution during assessment.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Solitary Pulmonary Nodule , Adenocarcinoma of Lung/diagnostic imaging , Adenocarcinoma of Lung/pathology , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Prognosis , Radiography , Solitary Pulmonary Nodule/diagnostic imaging , Solitary Pulmonary Nodule/pathology
8.
BMC Cancer ; 22(1): 919, 2022 Aug 25.
Article in English | MEDLINE | ID: mdl-36008784

ABSTRACT

OBJECTIVES: There are increasing numbers of studies of pleural tags (PTs). The purpose of this case series was to classify the PTs in patients with peripheral pulmonary adenocarcinoma based on radiologic-pathologic comparison and to study the prognosis. METHODS: The clinical, imaging, pathological and prognostic data of 161 patients with peripheral pulmonary adenocarcinoma in three hospitals were analyzed retrospectively. We classified PTs using computed tomography (CT) for pathologic comparison. RESULTS: According to the relationship between tumors and pleural on CT images, PTs were classified into four types: type 1, one or more linear pleural tag; type 2, one or more linear pleural tag with soft tissue component at the pleural end; type 3, one soft tissue cord-like pleural tag; type 4, directly abutting the visceral pleura, pulling or pushing the visceral pleura. In these PTs, the incidence of visceral pleural invasion (VPI) was high in type 2 (46.88%) and type 3 (56.41%) of PTs. Our prognostic analysis showed that micropapillary or solid histological subtype (HR = 5.766, 95% CI: 1.435-23.159, P = 0.014) and type 3 of PTs (HR = 11.058, 95% CI: 1.349-90.623, P = 0.025) were two independent risk factors for tumor progression. CONCLUSIONS: PT is a risk factor for poor prognosis in patients with peripheral pulmonary adenocarcinoma, the presence of which on CT images can remind us to provide patients with a more reasonable treatment.


Subject(s)
Adenocarcinoma of Lung , Adenocarcinoma , Lung Neoplasms , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/pathology , Adenocarcinoma of Lung/diagnostic imaging , Adenocarcinoma of Lung/pathology , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Neoplasm Invasiveness/pathology , Neoplasm Staging , Pleura/diagnostic imaging , Pleura/pathology , Prognosis , Retrospective Studies
9.
Cancer Med ; 11(15): 2969-2977, 2022 08.
Article in English | MEDLINE | ID: mdl-35801360

ABSTRACT

OBJECTIVE: Tertiary lymphoid structures (TLSs) are found in a variety of malignancies and affect the growth of tumors, but few studies have addressed their role in lung adenocarcinoma (LAC). We aimed to evaluate clinical features associated with TLSs in patients with LAC. METHODS AND MATERIALS: A collection of resected pulmonary nodules in patients with LAC was retrospectively analyzed. TLSs were quantified by their number per square millimeter tumor area (density) and by the degree of lymphocyte aggregation (maturity) in each case. The correlation between TLS density and maturity and clinical features was calculated. RESULTS: A total of 243 patients were selected, of whom 219 exhibited TLSs. The occurrence of TLSs was correlated with computed tomography (CT) features as follows: pure ground-glass nodules (pGGNs) (n = 43) was associated with a lower occurrence rate than part-solid nodules (PSNs) (n = 112) and solid nodules (SNs) were (n = 88) (p = 0.037). TLS density was correlated with age and CT features. Poisson regression showed higher TLS density in PSNs and SNs than in pGGNs (incidence rate ratio [IRR]: 3.137; 95% confidence interval [CI]: 1.35-7.27; p = 0.008 and IRR: 2.44; 95% CI: 1.02-5.85; p = 0.046, respectively). In addition, TLS density was higher in patients aged under 60 years than in those aged over 60 years (IRR: 0.605; 95% CI: 0.4-0.92; p = 0.018). The maturity of TLSs was higher in patients with higher tumor stages (p = 0.026). CONCLUSIONS: We demonstrated distinct profiles of TLSs in early LAC and their correlations with CT features, age, and tumor stages, which could help understand tumor progression and management.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Tertiary Lymphoid Structures , Adenocarcinoma of Lung/diagnostic imaging , Adenocarcinoma of Lung/pathology , Aged , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed/methods
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(3): 433-439, 2022 Jun.
Article in Chinese | MEDLINE | ID: mdl-35791941

ABSTRACT

Objective To improve the understanding and diagnostic accuracy of pulmonary mucoepidermoid carcinoma(PMEC) by analyzing the imaging and clinical characteristics.Methods The clinical and CT data of 27 cases of PMEC confirmed by histopathology in the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2020 were retrospectively analyzed,including the location,size,margin,density,enhancement characteristics,accompanying signs,and pathological grade.Results The 27 cases included 6(6/27,22.2%) of large airway type,14(14/27,51.9%) of hilar type,and 7(7/27,26.9%) of peripheral type.The CT manifestations of 20 cases of large airway and hilar PMEC were soft-tissue nodules or mass with clear boundary in the lumen of the trachea and main bronchi,including 6 cases of mild enhancement,4 cases of moderate enhancement,5 cases of marked enhancement,and 5 cases of uneven enhancement.Three of the 20 cases showed calcification.The 7 cases of peripheral PMEC showed soft-tissue nodules or masses in the lungs,including 3 cases of mild enhancement,1 case of moderate enhancement,and 3 cases of marked enhancement. Obstructive pneumonia or atelectasis and bronchiectasis with mucus plug formation occurred in 16(16/27,59.3%) cases,lymph node metastasis in 9(9/27,33.3%) cases,and multiple organ metastasis in 8(8/27,29.6%) cases.Age(t=-3.132,P=0.005),enlarged lymph node (χ2=9.281,P=0.003),and distant metastasis(χ2=7.816,P=0.008) were statistically significant in the low-grade group and high-grade group. Conclusion PMEC have some unique imaging features,and recognizing these signs is conducive to the differential diagnosis and the improvement of the diagnostic accuracy.


Subject(s)
Carcinoma, Mucoepidermoid , Lung Neoplasms , Carcinoma, Mucoepidermoid/diagnostic imaging , Child, Preschool , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Lymphatic Metastasis , Retrospective Studies , Tomography, X-Ray Computed/methods
11.
Phys Chem Chem Phys ; 24(21): 13156-13170, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35593151

ABSTRACT

Integrated gasification combined cycle (IGCC) is a promising clean technology for coal power generation; however, the high volatility and toxicity of arsenic pollutants (As2, As4, AsO and AsH3) released from an IGCC coal plant cause serious damage to human health and the ecological environment. Therefore, highly efficient adsorbents for simultaneous treatment of multiple arsenic pollutants are urgently needed. In this work, the adsorption characteristics and competitive adsorption behaviors of As2, As4, AsO, and AsH3 on four kinds of graphene-based single-atom iron adsorbents (Fe/GA) were systematically investigated through density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. The results suggest that single-vacancy Fe/GA doped with three nitrogen atoms has the largest adsorption ability for As2, As4, AsO and AsH3. The adsorption energies of As2, AsO and As4 on Fe/GA depend on both charge transfer and orbital hybridization, while the adsorption energy of AsH3 is mainly decided by electronic transfer. The adsorption differences of As2, As4, AsO and AsH3 on four Fe/GA adsorbents can be explained through the obvious linear relationship between the adsorption energy and Fermi softness. As2, As4, AsO and AsH3 will compete for adsorption sites when they exist on the same adsorbent surface simultaneously, and the adsorption capacities of AsO and As2 are relatively stronger. After the competitive adsorption between AsO and As2, AsO occupies the adsorption site at 300-900 K. This theoretical work suggests that Fe/GA is a promising adsorbent for the simultaneous removal of multiple arsenic pollutants with high adsorption capacity and low cost.


Subject(s)
Arsenic , Environmental Pollutants , Graphite , Water Pollutants, Chemical , Water Purification , Adsorption , Coal , Humans , Iron , Water Pollutants, Chemical/analysis , Water Purification/methods
12.
J Mol Model ; 28(4): 80, 2022 Mar 05.
Article in English | MEDLINE | ID: mdl-35247076

ABSTRACT

The poor stability of organic-inorganic hybrid perovskites hinders its commercial application, which motivates a need for greater theoretical insight into its binding mechanism. To date, the binding mode of organic cation and anion inside organic-inorganic hybrid perovskites is still unclear and even contradictory. Therefore, in this work based on density functional theory (DFT), the binding mechanism between organic cation and anion was systematically investigated through electronic structure analysis including an examination of the electronic localization function (ELF), electron density difference (EDD), reduced density gradient (RDG), and energy decomposition analysis (EDA). The binding strength is mainly determined by Coulomb effect and orbital polarization. Based on the above analysis, a novel 2D linear regression descriptor that Eb = - 9.75Q2/R0 + 0.00053 V∙EHL - 6.11 with coefficient of determination R2 = 0.88 was proposed to evaluate the binding strength (the units for Q, R0, V, and EHL are |e|, Å, bohr3, and eV, respectively), revealing that larger Coulomb effect (Q2/R0), smaller volume of perovskite (V), and narrower energy difference (EHL) between the lowest unoccupied molecular orbital (LUMO) of organic cation and the highest occupied molecular orbital (HOMO) of anion correspond to the stronger binding strength, which guides the design of highly stable organic-inorganic hybrid perovskites.

13.
Adv Mater ; 34(20): e2110123, 2022 May.
Article in English | MEDLINE | ID: mdl-35291046

ABSTRACT

Catalytic oxidation of NO and Hg0 is a crucial step to eliminate multiple pollutants from emissions from coal-fired power plants. However, traditional catalysts exhibit low catalytic activity and poor sulfur resistance due to low activation ability and poor adsorption selectivity. Herein, a single-atom Fe decorated N-doped carbon catalyst (Fe1 -N4 -C), with abundant Fe1 -N4 sites, based on a Fe-doped metal-organic framework is developed to oxidize NO and Hg0 . The results demonstrate that the Fe1 -N4 -C has ultrahigh catalytic activity for oxidizing NO and Hg0 at low and room temperature. More importantly, Fe1 -N4 -C exhibits robust sulfur resistance as it preferably adsorbs reactants over sulfur oxides, which has never been achieved before with traditional catalysts. Furthermore, SO2 boosts the catalytic oxidation of NO over Fe1 -N4 -C through accelerating the circulation of active sites. Density functional theory calculations reveal that the Fe1 -N4 active sites result in a low energy barrier and high adsorption selectivity, providing detailed molecular-level understanding for its excellent catalytic performance. This is the first report on NO and Hg0 oxidation over single-atom catalysts with strong sulfur tolerance. The outcomes demonstrate that single-atom catalysts are promising candidates for catalytic oxidation of NO and Hg0 enabling cleaner coal-fired power plant operations.

14.
Chemphyschem ; 23(7): e202100841, 2022 04 05.
Article in English | MEDLINE | ID: mdl-35199438

ABSTRACT

Inorganic metal halide perovskites, such as CsPbI3 , have recently drawn extensive attention due to their excellent optical properties and high photoelectric efficiencies. However, the structural instability originating from inherent ionic defects leads to a sharp drop in the photoelectric efficiency, which significantly limits their applications in solar cells. The instability induced by ionic defects remains unresolved due to its complicated reaction process. Herein, to explore the effects of ionic defects on stability, we develop a deep learning potential for a CsPbI3 ternary system based upon density functional theory (DFT) calculated data for large-scale molecular dynamics (MD) simulations. By exploring 2.4 million configurations, of which 7,730 structures are used for the training set, the deep learning potential shows an accuracy approaching DFT-level. Furthermore, MD simulations with a 5,000-atom system and a one nanosecond timeframe are performed to explore the effects of bulk and surface defects on the stability of CsPbI3 . This deep learning potential based MD simulation provides solid evidence together with the derived radial distribution functions, simulated diffraction of X-rays, instability temperature, molecular trajectory, and coordination number for revealing the instability mechanism of CsPbI3 . Among bulk defects, Cs defects have the most significant influence on the stability of CsPbI3 with a defect tolerance concentration of 0.32 %, followed by Pb and I defects. With regards to surface defects, Cs defects have the largest impact on the stability of CsPbI3 when the defect concentration is less than 15 %, whereas Pb defects act play a dominant role for defect concentrations exceeding 20 %. Most importantly, this machine-learning-based MD simulation strategy provides a new avenue to explore the ionic defect effects on the stability of perovskite-like materials, laying a theoretical foundation for the design of stable perovskite materials.


Subject(s)
Deep Learning , Sunlight
15.
Phys Chem Chem Phys ; 24(5): 3460-3469, 2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35076034

ABSTRACT

Perovskite solar cells (PSCs) have been intensively investigated and made great progress due to their high photoelectric conversion efficiency and low production cost. However, poor stability and the toxicity of Pb limit their commercial applications. It is particularly important to search for new non-toxic, high-stability perovskite materials. In this study, 760 Cs2B2+B'2+X6 (X = F, Cl, Br, I) inorganic halide double perovskites are screened based on high-throughput first-principles calculations to obtain an ideal perovskite material. The band gaps of this type of double perovskite are mainly determined by the elements X and B2+, decreasing monotonously with the increase in the atomic number of X (from F to I). We obtain 14 optimal and unreported materials with suitable band gaps as potential alternative materials for Pb-based photovoltaic absorbers in PSCs. This theoretical investigation can provide theoretical guidance for developing novel lead-free PSC materials.

16.
J Hazard Mater ; 421: 126639, 2022 Jan 05.
Article in English | MEDLINE | ID: mdl-34396974

ABSTRACT

Developing catalysts with high activity, durability, and water resistance for ozone decomposition is crucial to regulate the pollution of ozone in the troposphere, especially in indoor air. To overcome the shortcomings of metal oxide catalysts with respect to their durability and water resistance, Fe-Co double-atom catalyst (DAC) is proposed as a novel catalyst for ozone decomposition. Here, through a systematic study using density functional theory (DFT) calculations and microkinetic modeling, the adsorption and catalytic decomposition of O3 on Fe-Co DAC have been examined based on adsorption configuration, orbital hybridization, and electron transfer. Based on Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) reaction mechanisms, the mechanisms of ozone decomposition on Fe-Co DAC were explored by analyzing reaction paths and energy variations. To confirm the water-resistant of Fe-Co DAC, competitive adsorption behavior between O3 and dominant environmental gases was discussed through ab initio molecular dynamic (AIMD) simulation. The dominant reaction mechanism of ozone decomposition is L-H and the rate-determining step is the desorption of the first oxygen molecule from the surface of Fe-Co DAC which has an energy barrier of 0.78 eV. Due to this relatively low energy barrier and high turnover frequency (TOF), the optimal operation window of catalytic O3 decomposition on Fe-Co DAC is <500 K suggesting that catalytic decomposition of O3 on Fe-Co DAC can occur at room temperature. This theoretical study provides new insights for designing novel catalysts for ozone decomposition and fundamental guidance for subsequent experimental research.

17.
Curr Top Med Chem ; 22(12): 993-1008, 2022.
Article in English | MEDLINE | ID: mdl-34636313

ABSTRACT

Acquired immunodeficiency syndrome (AIDS), caused by the human immunodeficiency virus (HIV), is one of the leading causes of human deaths. The advent of different anti-HIV drugs has turned AIDS/HIV from a deadly infection to chronic and manageable disease. However, the development of multidrug-resistant viruses, along with the severe side effects of anti-HIV agents, has compromised their efficacy and limited the treatment options. Indoles, the most common frameworks in the bioactive molecules, represent attractive scaffolds for designing and developing novel drugs. Indole derivatives are potent inhibitors of HIV enzymes such as reverse transcriptase, integrase, and protease. Furthermore, some indole-based agents, like delavirdine, have already been applied in clinics or are under clinical evaluations for the treatment of AIDS/HIV, revealing that indole moiety is a useful template for the development of anti-HIV agents. This review focuses on the recent advancement in indole derivatives, including indole alkaloids, hybrids, and dimers with anti-HIV potential, covering articles published between 2010 and 2020. The chemical structures, structure-activity relationship, and mechanisms of action are also discussed.


Subject(s)
Acquired Immunodeficiency Syndrome , Anti-HIV Agents , HIV Infections , Acquired Immunodeficiency Syndrome/drug therapy , Anti-HIV Agents/chemistry , HIV Infections/drug therapy , Humans , Indoles/chemistry , Structure-Activity Relationship
18.
Chem Commun (Camb) ; 57(91): 12127-12130, 2021 Nov 16.
Article in English | MEDLINE | ID: mdl-34723294

ABSTRACT

Dual-atom Fe catalysts supported by three nitrogen atom doped graphene (Fe-TM/GP, where TM = Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) are explored for methane adsorption and activation. The addition of the second metal significantly tunes the properties of the catalysts. The main factor influencing methane adsorption is electron transfer. The second metal promotes methane adsorption by altering the electronic properties such as the band structure and charge transfer. A volcano-shaped relationship is found between the absolute value of adsorption energy and energy barrier at the heteroatom Fe-TM/GP. Fe-Ni/GP has the lowest energy barrier. Heteroatom Fe-TM/GP has a lower energy barrier than Fe-Fe/GP.

19.
Int J Mol Sci ; 22(15)2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34361016

ABSTRACT

Although small water clusters (SWCs) are important in many research fields, efficient methods of preparing SWCs are still rarely reported, which is mainly due to the lack of related materials and understanding of the molecular interaction mechanisms. In this study, a series of functional molecules were added in water to obtain small water cluster systems. The decreasing rate of the half-peak width in a sodium dodecyl sulfate (SDS)-water system reaches ≈20% at 0.05 mM from 17O nuclear magnetic resonance (NMR) results. Based on density functional theory (DFT) and molecular dynamics (MD) simulation calculation, it can be concluded that functional molecules with stronger negative electrostatic potential (ESP) and higher hydrophilicity have a stronger ability to destroy big water clusters. Notably, the concentrations of our selected molecule systems are one to two magnitudes lower than that of previous reports. This study provides a promising way to optimize aqueous systems in various fields such as oilfield development, protein stability, and metal anti-corrosion.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Molecular Dynamics Simulation , Sodium Dodecyl Sulfate/chemistry , Magnetic Resonance Spectroscopy , Static Electricity , Water/chemistry
20.
Phys Chem Chem Phys ; 23(25): 13971-13976, 2021 Jun 30.
Article in English | MEDLINE | ID: mdl-34143174

ABSTRACT

Sulfur-containing iron materials such as sulfidized nanoscale zerovalent iron (SNZVI) have shown outstanding water remediation performance in many recent studies, which is largely attributed to its high hydrophobicity compared to that of NZVI. However, the role of sulfur in the reactions, and the origin of the hydrophobicity of SNZVI, were still unclear. In this paper, for the first time, we conducted ab initio molecular dynamics simulation using an explicitly solvated model on both Fe and S-containing Fe surfaces, to explore the hydrophobicity of S-containing Fe materials. We found that the high hydrophobicity of these S-containing Fe surfaces originates from the hydrophobic nature of S: both doping S on top of the Fe surface and inserting S onto an Fe surface can significantly improve the surface hydrophobicity by increasing the distance between the water layer and the Fe surface. This exposes empty Fe sites which do not interact with water and in turn reduces hydrogen evolution. To compare with the theoretical analysis, we experimentally analyzed the hydrophobicity of both NZVI and SNZVI surfaces, leading to a good agreement with our theoretical analysis. We then theoretically show that the doping of other p-block elements (e.g., N and P) to iron surfaces can also create a hydrophobic phenomenon. Most importantly, this study points out that the potential contribution of hydrophobicity to the reactivity on liquid-phase reaction materials should not be ignored in the mechanistic analysis.

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