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1.
Phys Chem Chem Phys ; 26(14): 10494-10505, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38517057

ABSTRACT

Hexagonal boron nitride possesses a unique layered structure, high specific surface area and similar electronic properties as graphene, which makes it not only a promising catalyst support, but also a highly effective metal-free catalyst in the booming field of green chemistry. Reactions involving small molecules (e.g., oxygen, low carbon alkanes, nitrogen and carbon dioxide) have always been a hot topic in catalytic research, especially associated with the adsorption and activation regime of different forms of small molecules on catalysts. In this review, we have investigated the adsorption of different small molecules and the relevant activation mechanisms of four typical chemical bonds (OO, C-H, NN, CO) on hexagonal boron nitride. Recent progress on approaches adopted to enhance the activation capacity such as doping, defect engineering and heterostructuring are summarized, highlighting the potential applications of nonmetallic hexagonal boron nitride catalysts in various reactions. This comprehensive investigation offers a reference point for the enhanced mechanistic understanding and future design of effective and sustainable catalytic systems based on boron nitride.

2.
Adv Sci (Weinh) ; 11(2): e2307862, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37985651

ABSTRACT

More recently, soft actuators have evoked great interest in the next generation of soft robots. Despite significant progress, the majority of current soft actuators suffer from the lack of real-time sensory feedback and self-control functions, prohibiting their effective sensing and multitasking functions. Therefore, in this work, a near-infrared-driven bimorph membrane, with self-sensing and feedback loop control functions, is produced by layer by layer (LBL) assembling MXene/PDDA (PM) onto liquid crystal elastomer (LCE) film. The versatile integration strategy successfully prevents the separation issues that arise from moduli mismatch between the sensing and the actuating layers, ultimately resulting in a stable and tightly bonded interface adhesion. As a result, the resultant membrane exhibited excellent mechanical toughness (tensile strengths equal to 16.3 MPa (||)), strong actuation properties (actuation stress equal to 1.56 MPa), and stable self-sensing (gauge factor equal to 4.72) capabilities. When applying the near-infrared (NIR) laser control, the system can perform grasping, traction, and crawling movements. Furthermore, the wing actuation and the closed-loop controlled motion are demonstrated in combination with the insect microcontroller unit (MCU) models. The remote precision control and the self-sensing capabilities of the soft actuator pave a way for complex and precise task modulation in the future.

3.
Chemosphere ; 331: 138748, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37088209

ABSTRACT

The fenton-like process based on peroxymonosulfate (PMS) activation is considered as a promising strategy for the removal of organic pollutants. However, the development of efficient photocatalysts for PMS activation remains challenging. Herein, copper-iron prussian blue analogue (CunFe1-PBA, n = 1, 2, 3, 4) nanomaterials were first fabricated through a simple combination of co-precipitation and calcination processes. The as-synthesized CunFe1-PBA composite catalyst was used to activate PMS for the degradation of endocrine disruptor bisphenol S (BPS). As the result, Cu3Fe1-PBA calcined at 300 °C (Cu3Fe1-PBA*300 °C) mainly composed of CuFe2O4 and CuO showed a higher catalytic activity for activating PMS for BPS degradation than those of CunFe1-PBA composite. Additionally, Cu3Fe1-PBA*300 °C/PMS system was suitable for degradation of BPS at 400 mg/L catalyst or PMS and wide pH ranges from 3 to 11 while coexisting inorganic anions (SO42-, NO3-, and HCO3-) and humic acid all inhibited the reaction. Radical trapping experiment, electron paramagnetic resonance (EPR), and X-ray photoelectron spectroscopy (XPS) proved that Cu and Fe could regulate the charge balance through changes of valence state, and active PMS to produce free radicals effectively, especially the production of 1O2. Furthermore, the analysis of the BPS intermediates of degradation was carried out by ultra-performance liquid chromatography-mass spectrometry, and two degradation pathways of BPS were proposed. In summary, this work provides a facile avenue to design efficient catalysts to activate PMS for the degradation of emerging organic pollutants in water remediation.


Subject(s)
Environmental Pollutants , Peroxides , Peroxides/chemistry , Ferrocyanides
4.
Am J Transl Res ; 14(10): 7467-7476, 2022.
Article in English | MEDLINE | ID: mdl-36398253

ABSTRACT

OBJECTIVE: To explore the effects of teicoplanin on pulmonary infection after chemotherapy for hematologic malignancies. METHODS: In the present retrospective study, 64 patients with pulmonary infection, who underwent chemotherapy for hematologic malignancies at Anhui No.2 Provincial People's Hospital from September 2019 to September 2021, were selected as an infection group, and their clinical data were retrospectively analyzed. Meanwhile, 30 patients without pulmonary infection after chemotherapy for hematologic malignancies were selected as a reference group. Patients in the infection group were subdivided into control and treatment groups (n=32 each) according to the different therapeutic regimens. The control group was given routine treatment with norvancomycin, while the treatment group was given teicoplanin combined with norvancomycin. The therapeutic effects, bacterial clearance rate, recovery time, clinical pulmonary infection score (CPIS), inflammatory factors and adverse reactions were compared between the two groups. The risk factors of pulmonary infection after treatment for hematologic malignancies were analyzed. RESULTS: The treatment group exhibited higher total therapeutic effect and higher bacterial clearance rate than the control group (P < 0.05). The treatment group had shorter time to the recovery of white blood cell (WBC) count, time to the disappearance of cough and sputum, time to return to normal body temperature, and length of stay than the control group (P < 0.05). One month post-treatment, the levels of C-reactive protein, tumor necrosis factor-α, interleukin-1ß, and procalcitonin in the treatment group were lower than those in the control group (P < 0.05). The CPISs at 7, 14, and 30 days after treatment were lower in the treatment group than those in the control group (P < 0.05). Compared with the reference group, the infection group had higher rate of diabetes, higher rate of glucocorticoid use, longer time of agranulocytosis, longer hospital stay and lower WBC count (P < 0.05). Multivariate Logistic regression analysis showed that agranulocytosis time, diabetes mellitus and glucocorticoid use were independent risk factors for pulmonary infection after treatment for hematologic malignancies (P < 0.05), and that higher WBC was a protective factor (P < 0.05). CONCLUSION: Teicoplanin in the treatment of pulmonary infection after chemotherapy for hematologic malignancies can improve the therapeutic effects, effectively clear bacteria, shorten the recovery time and reduce the inflammatory response.

5.
Sci Rep ; 12(1): 7927, 2022 May 13.
Article in English | MEDLINE | ID: mdl-35562539

ABSTRACT

In this work, perovskite solar cells (PSCs) with different transport layers were fabricated to understand the hysteresis phenomenon under a series of scan rates. The experimental results show that the hysteresis phenomenon would be affected by the dielectric constant of transport layers and scan rate significantly. To explain this, a modified Poisson and drift-diffusion solver coupled with a fully time-dependent ion migration model is developed to analyze how the ion migration affects the performance and hysteresis of PSCs. The modeling results show that the most crucial factor in the hysteresis behavior is the built-in electric field of the perovskite. The non-linear hysteresis curves are demonstrated under different scan rates, and the mechanism of the hysteresis behavior is explained. Additionally, other factors contributing to the degree of hysteresis are determined to be the degree of degradation in the perovskite material, the quality of the perovskite crystal, and the materials of the transport layer, which corresponds to the total ion density, carrier lifetime of perovskite, and the dielectric constant of the transport layer, respectively. Finally, it was found that the dielectric constant of the transport layer is a key factor affecting hysteresis in perovskite solar cells.

6.
Environ Sci Pollut Res Int ; 28(2): 2052-2062, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32865683

ABSTRACT

Lanthanum-modified bentonite (LMB, Phoslock®) is a well-known capping agent for phosphorus immobilization in sediments. Herein, LMB was used to immobilize As in sediments. Batch capacity experiments for arsenate and arsenite adsorption were carried out to obtain adsorption isotherms and kinetics using the Langmuir and Freundlich model calculations. High-resolution (HR) diffusive gradients in thin films (DGT) were applied to monitor the changes of weakly bound As fraction near sediment-water interface (SWI). The interaction of As(III) and As(V) with LMB was influenced by pH and initial mineral composition. As(V) was more obviously adsorbed than As(III) at pH 4 to 9, with mean adsorption of 3.89 mg g-1 and 0.04 mg g-1, respectively, while at pH > 9 As(III) was preferentially adsorbed. After LMB amendment for 2 months, the maximum As removal efficiency in the pore and overlying water reached 84.5% and 99.3%, respectively. The capping agent remained stable in the top sediments, while the maximum DGT labile As content decreased to 0.89 and 0.51 µg L-1 in dosage-and time-treatments. The As concentration inflection point moved down to a deeper layer. As species changed from labile exchangeable-As to Fe-oxide-bound and residual As. The proportion of mobile As finally decreased to 10.5% of the total As in the upper 20-mm layer sediment. The increase of Kd (the distribution coefficient at SWI) and k1 (adsorption rate constant) and the decrease of Tc (response time of (de)sorption) in the DGT-induced fluxes model (DIFS) indicated the time-dependent impediment of As release from the sediment due to LMB immobilization.


Subject(s)
Arsenic , Water Pollutants, Chemical , Bentonite , Geologic Sediments , Lakes , Lanthanum , Phosphorus , Water Pollutants, Chemical/analysis
7.
Zhongguo Zhen Jiu ; 39(11): 1193-8, 2019 Nov 12.
Article in Chinese | MEDLINE | ID: mdl-31724356

ABSTRACT

OBJECTIVE: To observe the correlation between referred pain distribution and acupoint sensitization in patients with intestinal diseases. METHODS: In clinical research, 443 patients from 8 hospitals were recruited, including the outpatients and inpatients of Crohn's disease (n=143), ulcerative colitis (n=108), chronic appendicitis (n=87) and other intestinal diseases (n=105). The site with tenderness on the body surface and the morphological changes of local skin were observed and recorded in the patients. Using a sensory tenderness instrument, the pain threshold at the sensitization point was measured in 60 patients with ulcerative colitis. In animal experiment, SD rats were used and divided into a enteritis group (n=8), in which the enteritis model were established, and a control group (n=3), in which no any intervention was given. After the injection of Evans blue (EB) at caudal vein, the blue exudation points on the body surface were observed and the distribution rule was analyzed statistically. RESULTS: The referred pain on the body surface in the patients with intestinal diseases was mainly located in the lower abdomen (93.9%, 416/443), the lumbar region (70.9%, 314/443) and the lower legs (33.0%, 146/443). The diameter of tenderness region was 1.5 to 2.5 cm. Compared with the region without sensitization, the pain threshold of the sensitization point in the patients with ulcerative colitis was reduced significantly (P<0.001). The referred pain on the body surface in the patients with appendicitis was located in the right lower abdomen (97.7%, 85/87), the waist and back (54.0%, 47/87) and the right lower limbs on the medial side (71.3%, 62/87). The tenderness region was 1 to 2 cm in diameter and was irregular in form. After modeling of enteritis in the rats, the EB exudation points were visible from T12 to L2. CONCLUSION: Intestinal diseases induce referred pain on the body surface where is the same as or adjacent to the location of the spinal segment corresponding to the affected intestinal section. These sensitization regions are related to the locations of acupoints.


Subject(s)
Acupuncture Points , Intestinal Diseases , Pain, Referred , Animals , Colitis, Ulcerative , Humans , Pain Threshold , Pain, Referred/diagnosis , Pain, Referred/therapy , Rats , Rats, Sprague-Dawley , Sensation
8.
Zhen Ci Yan Jiu ; 43(5): 277-84, 2018 May 25.
Article in Chinese | MEDLINE | ID: mdl-29888560

ABSTRACT

OBJECTIVE: To observe the correlation between the referred pain regions of stable angina pectoris (SAP) and the acupoints in coronary heart disease (CHD) patients and to investigate the rule of regional sensitized point distribution in rats. METHODS: A total of 1 046 CHD patients with SAP from 8 hospitals in China were recruited in the present study. The tenderness was palpated along the left and right chest, back, shoulder, upper limb, etc. by a specially-assigned researcher in each hospital. Among them, 77 patients accepted pain threshold (PT) measurement by using a hand-held esthesiometer. In animal experiments, 14 SD rats were subjected to occlusion of the left anterior descending branch of the left coronary artery for 4 h for establishing myocardial ischemia (MI) model, and other 4 normal rats were used as the sham-operation control group. Four hours after MI, all the rats accepted tail venous injection of 5% Evans blue (50 mg/kg) for examining the distribution of the blue dye exudation spots at the body surface where the mechanical PT was also detected by a von Frey. RESULTS: In 1 046 CHD patients, 987 (94.36%) were found to have at least one tenderness spot. The tenderness spots were found at the left chest (87.47%), right chest (13.67%), left arm (ulnar side, 41.30%), right upper limb (4.68%), left shoulder back (30.21%), right shoulder back (7.07%), etc., accompanied with rash or pigmentation, subcutaneous induration, cord-like tissue contracture, skin sag, etc. The mechanical PT level was significantly lower at the tenderness spots of the left upper limb than at non-tender points of the right upper limb in CHD patients (P<0.001). Tenderness and cutaneous abnormal changes in angor pectoris patients distributed mostly on the left chest, back, shoulder and upper limb, and some also on the right. Tender points scattered on, near or outside acupoints. A similar distribution of the blue exudation spots and lower mechanical PT spots were found in MI rats, but not in sham-MI rats. CONCLUSION: In the case of MI, a regular "referred sensitization" response frequently occurs in the dermatomere area innervated by the corresponding segments (T 1-T 5) in both CHD patients and MI rats, which may be closely associated with the formation of acupoints in ancient China.


Subject(s)
Angina, Stable , Myocardial Ischemia , Pain, Referred , Acupuncture Points , Animals , Rats , Rats, Sprague-Dawley
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(1): 214-8, 2012 Feb.
Article in Chinese | MEDLINE | ID: mdl-22391200

ABSTRACT

Aplastic anemia (AA) is an autoimmune disease characterized by destruction of hematopoietic tissue resulting in hyperfunction of effector T-lymphocytes. Recent studies indicate that Th17 and Treg cells are functionally antagonistic each other, and the increase of Th17 cells and decrease of Treg cells are closely related with AA. In vivo experiments showed that both anti-IL-17 treatment and Treg cell infusion can protect against immune-mediated bone marrow failure in mouse with AA. This review summarizes the recent progress of study on imbalance of Th17/Treg cells in AA, so as to explore the pathogenesis of AA and provide approach to clinical treatment. The main problems that are discussed in this review include biological characteristics of Th17/Treg cells, the regulation of Th17/Treg cell balance and related cytokines, the relationship between Th17/Treg cells and AA.


Subject(s)
Anemia, Aplastic/immunology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Anemia, Aplastic/pathology , Humans
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