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2.
J Formos Med Assoc ; 2023 Dec 28.
Article in English | MEDLINE | ID: mdl-38158260

ABSTRACT

Vitiligo is a common acquired disease of pigment loss. In lesions recalcitrant to non-invasive treatment, transplantation of cultured autologous melanocytes is an emerging choice. Conventionally, the recipient site is often prepared by laser-mediated or mechanical dermabrasion. Such preparation procedures have disadvantages including prolonged transplantation duration, long period for reepithelialization and potential scarring. We propose a method of preparing recipient sites by psoralen and controlled ultraviolet A (PUVA)-induced blistering followed by transplanting suspended melanocytes. We introduced this method in 10 patients with segmental vitiligo on their recipient site 3 to 5 days before transplantation and blistering developed in 2 to 3 days afterwards. On the day of transplantation, the blister roof could be peeled off easily without bleeding and the recipient site preparation could be completed in 20 min. The recipient site became reepithelialized within 1 week. Progressive repigmentation was observed for up to 6 months, with an average of 65.06% repigmentation in the recipient site without scarring at the end of follow-up. Hence, preparation of the recipient site by controlled PUVA-induced sunburn-like blistering can potentially facilitate melanocyte transplantation and prevent scarring.

3.
Angew Chem Int Ed Engl ; 62(35): e202305985, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37403425

ABSTRACT

Covalent organic frameworks (COFs) have wide-ranging applications, and their host-guest interactions play an essential role in the achievement of COF functions. To investigate these host-guest interactions, it is necessary to locate all atoms, especially hydrogen atoms. However, it is difficult to determine the hydrogen atomic positions in COFs because of the complexities in synthesizing high-quality large single crystals. Three-dimensional electron diffraction (3D ED) has unique advantages for the structural determination of nanocrystals and identification of light atoms. In this study, it was demonstrated for the first time that the hydrogen atoms of a COF, not only on the framework but also on the guest molecule, can be located by 3D ED using continuous precession electron diffraction tomography (cPEDT) under cryogenic conditions. The host-guest interactions were clarified with the location of the hydrogen atoms. These findings provide novel insights into the investigation of COFs.

4.
J Am Chem Soc ; 145(20): 11276-11281, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37167629

ABSTRACT

Dimensional isomers, defined in reticular chemistry as frameworks consisting of identical molecular building blocks but extended in two or three dimensions (2D or 3D), are an important type of framework isomers that have never been isolated. Herein, we report the crystallization of dimensional isomers in covalent organic frameworks (COFs) for the first time. By polymerization of the same molecular building blocks at different temperatures, both 2D and 3D COFs were successfully constructed due to the temperature-induced conformational changes of precursors from planar to tetrahedral. In addition, the non-fluorescent 2D COF can be gradually converted into the fluorescent 3D COF by increasing the temperature under solvothermal conditions. Therefore, it is reasonable to crystallize the dimensional isomers of reticular materials by controlling the conformation of molecular building blocks, and more examples can be expected. Since the obtained dimensional isomers show different properties and functions, this work will definitely motivate us to design reticular materials for target applications in the future.

5.
Cureus ; 15(4): e38153, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37252473

ABSTRACT

Solitary extramedullary plasmacytomas are an exceedingly rare form of malignant neoplasms characterized by a single localized mass located in any soft tissue that consists of abnormal plasma cells. This type of tumor is characterized by the absence of plasmacytosis on bone marrow biopsy, the absence of other lesions on imaging, and no clinical signs of multiple myeloma. They usually present with mass effect, so the clinical picture varies based on the location of the tumor. In cases where the tumor is located in the gastrointestinal tract, patients may experience abdominal pain, small bowel obstruction, or gastrointestinal bleeding. The diagnostic process typically involves imaging to identify the tumor and its location, followed by a biopsy of the lesion with subsequent immunohistochemical analysis, as well as fluorescence in situ hybridization, and finally, bone marrow biopsy. Treatment options vary depending on the tumor's location and may include radiation therapy, surgical resection, and chemotherapy. Currently, radiation therapy is the preferred first-line treatment, with the best outcomes reported in the literature. Surgery is also frequently used and is often followed by radiation therapy. While chemotherapy has not been shown to have significant benefits, the available data is insufficient, and further studies are required to make better conclusions. Disease progression is often associated with transformation to multiple myeloma, but due to the rarity of the disease, data is limited, and it remains unclear if other forms of progression exist.   We report a case of a 63-year-old male who presented to the hospital with symptoms of abdominal pain, nausea, and vomiting. A computed tomography scan revealed a mass causing bowel obstruction, which was subsequently resected and evaluated by pathology. The final diagnosis was determined to be a solitary extramedullary plasmacytoma. Since the margins of the resected mass were clear, the patient was managed with solely clinical observation. Approximately eight months later, the patient was diagnosed with T-cell anaplastic large-cell lymphoma, ultimately leading to his passing 15 months after the initial diagnosis of solitary extramedullary plasmacytoma. We present this case to increase awareness of the rare condition of solitary extramedullary plasmacytoma and to highlight the potential association with T-cell anaplastic large-cell lymphomas, as demonstrated in this patient's case. Given the possibility of malignant transformation, close monitoring is warranted in similar cases.

6.
Cureus ; 15(4): e37793, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37214012

ABSTRACT

Paraganglioma is a rare type of neuroendocrine tumor with variable clinical presentations, making diagnosis relatively challenging. In this report, we present a case of retroperitoneal paraganglioma in a patient who experienced intermittent episodes of dizziness and chest pain. Imaging studies conducted during the patient's hospitalization revealed the presence of a lesion in the upper region of the right kidney, as well as a mass in the left retroperitoneal area that was suspected to be a paraganglioma. Biochemical studies were collected, including 24-hour urine metanephrines, urine catecholamines, urine cortisol, plasma metanephrines, renin, and aldosterone. However, it took an extended period of time for these results to come back. Given high clinical suspicion, alpha-blockade was initiated without a definite diagnosis of paraganglioma. Ultimately, the patient underwent tumor resection and the final pathology confirmed paraganglioma. The pathology of the contralateral renal mass showed oncocytoma. This case serves as an illustration of the difficulties that can arise when diagnosing and treating undiagnosed paragangliomas within a community healthcare setting.

7.
Nat Chem ; 15(6): 841-847, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37037913

ABSTRACT

A core feature of covalent organic frameworks (COFs) is crystallinity, but current crystallization processes rely substantially on trial and error, chemical intuition and large-scale screening, which typically require harsh conditions and low levels of supersaturation, hampering the controlled synthesis of single-crystal COFs, particularly on large scales. Here we report a strategy to produce single-crystal imine-linked COFs in aqueous solutions under ambient conditions using amphiphilic amino-acid derivatives with long hydrophobic chains. We propose that these amphiphilic molecules self-assemble into micelles that serve as dynamic barriers to separate monomers in aqueous solution (nodes) and hydrophobic compartments of the micelles (linkers), thereby regulating the polymerization and crystallization processes. Disordered polyimines were obtained in the micelle, which were then converted into crystals in a step-by-step fashion. Five different three-dimensional COFs and a two-dimensional COF were obtained as single crystals on the gram scale, with yields of 92% and above.

8.
J Am Acad Dermatol ; 88(1): 71-78, 2023 01.
Article in English | MEDLINE | ID: mdl-30703455

ABSTRACT

BACKGROUND: Data on predictors and time to relapse in patients with psoriasis who discontinue therapy in a real-world setting are scarce. OBJECTIVE: To investigate predictors of relapse after withdrawal of ustekinumab in patients with psoriasis. METHOD: This study screened 500 patients with psoriasis who received ustekinumab (669 treatment episodes) between 2011 and 2018. Overall, 202 patients (accounting for 304 treatment episodes) who had responded to therapy and were withdrawn from ustekinumab treatment were included. RESULTS: The cumulative probabilities of being relapse-free at 6, 12, 18, 24, and 36 months after withdrawal from ustekinumab treatment were 49.3%, 12.6%, 5.3%, 4.7%, and 1.6%, respectively. Multivariate regression analyses with a generalized estimating equation showed that after adjustments, biologic-naive status, maximum improvement in Psoriasis Area and Severity Index during ustekinumab treatment, time to achieve a 50% improvement in baseline Psoriasis Area and Severity Index score after initiation of ustekinumab, family history of psoriasis, chronic kidney disease, and immunosuppressant use while not taking ustekinumab were significant predictors of time to relapse following discontinuation of ustekinumab. LIMITATION: Nonrandomized allocation of duration of treatment and follow-up. CONCLUSION: Given the high rates of relapse, withdrawal of ustekinumab from patients with well-controlled psoriasis cannot be recommended.


Subject(s)
Psoriasis , Ustekinumab , Humans , Ustekinumab/therapeutic use , Etanercept , Adalimumab , Psoriasis/drug therapy , Immunosuppressive Agents , Recurrence , Treatment Outcome , Severity of Illness Index
9.
Chemistry ; 28(63): e202202170, 2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36066438

ABSTRACT

Stable extra-large-pore zeolites are desirable for industrial purposes due to their ability to accommodate bulky reactants and diffusion through channels. Although there are several extra-large pore zeolites reported, stable ones are rare. Thus, their stabilization is a feasible strategy for industrial applications. Here, an extra-large-pore zeolite EWT with boron substitution is presented, and the resulting zeolite B-RZM-3 increased the thermal stability from 600 °C in its silica form to 850 °C. The crystal structure, determined by combining continuous rotation electron diffraction (cRED) and powder X-ray diffraction (PXRD), shows that B atoms preferentially substitute the interrupted (HO)T(OT)3 (Q3 ) sites and are partially converted into 3-coordination to relax framework deformation upon heating. After Al-reinsertion post-treatment, Al-B-RZM-3 shows higher ethylbenzene selectivity and ethylene conversion rate per mol acid site than commercial ZSM-5 and Beta zeolite in benzene alkylation reaction. Synthesizing extra-large-pore zeolite in borosilicate form is a potential approach to stabilize interrupted zeolites for commercial applications.

10.
Molecules ; 27(17)2022 Aug 31.
Article in English | MEDLINE | ID: mdl-36080393

ABSTRACT

EWT zeolite belongs to ultra-large pore zeolite with the 10MR and 21MR channels, which has good thermal stability, certain acid strength and good application prospects in petroleum refining and petrochemical reactions. However, EWT zeolite has fewer medium/strong acid sites, especially Brönsted acid sites, which makes it difficult to apply to acid-catalyzed reactions. The regulation of acid amount and distribution was achieved by boron and aluminum substitution into the siliceous framework of EWT. The physico-chemical properties of the samples were characterized by XRD, SEM, N2 adsorption-desorption, XRF, ICP, Py-IR, NH3-TPD and 11B & 27Al & 29Si MAS NMR. The results show that quantities of boron and aluminum elements can occupy the framework of [B,Al]-EWT to increase the density of medium and strong acid centers, with more acidity and Brönsted acid centers than EWT zeolite. In the reaction of glycerol with cyclohexanone, the conversion of the sample (U-90-08-10/U-90-H-HCl) is significantly higher than that of the EWT sample, approaching or exceeding the Beta zeolite. A catalytic activity study revealed a direct correlation between the Brönsted acidic site concentration and the activity of the catalyst. The U-90-08-10-H catalyst was also considerably stable in the catalytic process. This work shows, for the first time, that extra-large pore zeolites can be used in industrial acid-catalytic conversion processes with excellent catalytic performance.

11.
Natl Sci Rev ; 9(6): nwac079, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35673533

ABSTRACT

The effects of nanoconfined water and the charge storage mechanism are crucial to achieving the ultrahigh electrochemical performance of two-dimensional transition metal carbides (MXenes). We propose a facile method to manipulate nanoconfined water through surface chemistry modification. By introducing oxygen and nitrogen surface groups, more active sites were created for Ti3C2 MXene, and the interlayer spacing was significantly increased by accommodating three-layer nanoconfined water. Exceptionally high capacitance of 550 F g-1 (2000 F cm-3) was obtained with outstanding high-rate performance. The atomic scale elucidation of the layer-dependent properties of nanoconfined water and pseudocapacitive charge storage was deeply probed through a combination of 'computational and experimental microscopy'. We believe that an understanding of, and a manipulation strategy for, nanoconfined water will shed light on ways to improve the electrochemical performance of MXene and other two-dimensional materials.

12.
Angew Chem Int Ed Engl ; 61(24): e202203584, 2022 Jun 13.
Article in English | MEDLINE | ID: mdl-35343628

ABSTRACT

The development of novel zeolite-like materials with large channel windows and high stability is of importance but remains a tremendous challenge. Herein, we report the first example of a 3D covalent organic framework with zeolitic network, namely the zeolitic organic framework (ZOF). By combining two kinds of tetrahedral building blocks with fixed or relatively free bond angles, ZOF-1 with the zeolitic crb net has been successfully synthesized. Its structure was determined by the single-crystal 3D electron diffraction technique. Remarkably, ZOF-1 shows high chemical stability, large pore size (up to 16 Å), and excellent specific surface area (≈2785 m2 g-1 ), which is superior to its analogues with the same network, including traditional aluminosilicate zeolites and zeolitic imidazole frameworks. This study thus opens a new avenue to construct zeolite-like materials with pure organic frameworks and will promote their potential applications in adsorption and catalysis for macromolecules.

13.
Angew Chem Int Ed Engl ; 61(2): e202113852, 2022 Jan 10.
Article in English | MEDLINE | ID: mdl-34755920

ABSTRACT

Three-dimensional covalent organic frameworks (3D COFs) have gained increasing attention for their attractive features. However, the development of 3D COFs is strongly restricted, mainly due to their synthetic difficulty and complicated structure determination. Post-synthetic modification, which can avoid these problems by incorporating functional moieties into a predetermined framework, provides an alternative way to construct 3D COFs with specific functions. Herein, we report the designed synthesis and characterization of a series of highly crystalline 3D COFs with different loadings of ethynyl groups. Notably, these alkyne-tagged 3D COFs provide a platform for targeted anchoring various specific groups onto the pore walls via click reactions. Moreover, the pore surface engineering can accordingly change their properties, for example, the obtained click products exhibited higher CO2 /N2 selectivity. We describe a simple but powerful strategy to build functional 3D COFs, which will certainly advance them for a ranging of interesting applications in the future.

14.
Nat Nanotechnol ; 16(5): 599-605, 2021 May.
Article in English | MEDLINE | ID: mdl-33619408

ABSTRACT

Layered lithium cobalt oxide (LiCoO2, LCO) is the most successful commercial cathode material in lithium-ion batteries. However, its notable structural instability at potentials higher than 4.35 V (versus Li/Li+) constitutes the major barrier to accessing its theoretical capacity of 274 mAh g-1. Although a few high-voltage LCO (H-LCO) materials have been discovered and commercialized, the structural origin of their stability has remained difficult to identify. Here, using a three-dimensional continuous rotation electron diffraction method assisted by auxiliary high-resolution transmission electron microscopy, we investigate the structural differences at the atomistic level between two commercial LCO materials: a normal LCO (N-LCO) and a H-LCO. These powerful tools reveal that the curvature of the cobalt oxide layers occurring near the surface dictates the structural stability of the material at high potentials and, in turn, the electrochemical performances. Backed up by theoretical calculations, this atomistic understanding of the structure-performance relationship for layered LCO materials provides useful guidelines for future design of new cathode materials with superior structural stability at high voltages.

15.
J Am Acad Dermatol ; 85(2): 337-344, 2021 08.
Article in English | MEDLINE | ID: mdl-31821860

ABSTRACT

BACKGROUND: The increasing use of biologics is accompanied by a risk of hepatitis B (HBV) and C virus (HCV) reactivation. OBJECTIVE: To determine the predictors of HBV and HCV reactivation in patients with psoriasis receiving biologics. METHODS: This study screened 2060 patients with psoriasis (3562 treatment episodes) who were taking biologics from 2009 to 2018. There were 359 patients with psoriasis with HBV (561 treatment episodes) and 61 with HCV infection (112 treatment episodes). RESULTS: During 8809 and 1522 person-months of follow-up, 88 treatment episodes for HBV involved HBV reactivation, and 14 episodes of HCV involved reactivation. The reactivation rate was significantly higher in treatment episodes of chronic HBV infection than in that of occult HBV (34.3% vs 3.2%, P = .001) and resolved HBV (34.3% vs 5.0%, P < .001). The multivariate analysis revealed that being hepatitis B surface antigen seropositive, being hepatitis B e-antigen seropositive, and tumor necrosis factor-α-inhibitor therapy were risk factors for HBV reactivation, whereas antiviral prophylaxis was effective in reducing the risk of HBV reactivation. No predictors were significantly associated with HCV reactivation. LIMITATIONS: Observational design and a lack of a comparison group. CONCLUSION: Patients with psoriasis on biologics have a risk of HBV and HCV reactivations, particularly those who are seropositive for hepatitis B surface antigen and hepatitis B e-antigen and undergoing tumor necrosis factor-α-inhibitor therapy.


Subject(s)
Biological Products/therapeutic use , Hepacivirus/physiology , Hepatitis B virus/physiology , Psoriasis/drug therapy , Psoriasis/virology , Virus Activation , Adult , Cohort Studies , Female , Humans , Male , Middle Aged , Time Factors
16.
Front Mol Biosci ; 8: 821927, 2021.
Article in English | MEDLINE | ID: mdl-35198600

ABSTRACT

The crystalline sponge method has shown to be a novel strategy for the structure determination of noncrystalline, oily, or trace amount of a compound. A target compound was absorbed and oriented orderly in the pregrown porous crystal for x-ray diffraction analysis. However, the diffusion in the micron-sized crystals is rather difficult. Lots of trial-and-error experiments are needed to optimize the guest-soaking process and to improve data quality. Nanocrystals are better in diffusion, yet it could not conduct a single crystal x-ray diffraction (SCXRD) analysis. Three-dimensional electron diffraction (3D-ED) is a powerful diffraction tool for the structure determination of small crystals. In this work, we successfully carried out the crystalline sponge method by 3D-ED technique using {(ZnI2)3-[2,4,6-tris(4-pyridyl)-1,3,5-triazine]2·x(guest)}n (1-Guest) porous complex nanocrystals. On account of the better diffuse ability of nanocrystals, the time needed for solvent exchange and guest soaking protocols are shortened 50-fold faster versus the original protocol. The crystal structure of the crystalline sponge incorporated with three different guests was fully resolved using a merged dataset. The structure model was identical to previously reported ones using x-ray, showing that the accuracy of the 3D-ED was comparable with SCXRD. The refinement results can also give the precise occupancy of the guest molecule soaked in the porous crystal. This work not only provides a new data collection strategy for crystalline sponge method but also demonstrates the potential of 3D-ED techniques to study host-guest interaction by solving the fine structure of porous material.

17.
J Occup Environ Med ; 62(8): e442-e448, 2020 08.
Article in English | MEDLINE | ID: mdl-32568819

ABSTRACT

OBJECTIVE: Compare the 2016 Federal Motor Carrier Safety Administration (FMCSA) and 2006 Joint Task Force (JTF) Guidelines for commercial drivers' obstructive sleep apnea (OSA) screening. METHODS: Retrospective review of all commercial driver medical examinations performed in 2017 at an academic occupational medicine clinic. Screening criteria from both the JTF and FMCSA were applied, separately, and jointly. Statistical tests were applied as appropriate. RESULTS: Applying the FMCSA or JTF criteria separately to 706 commercial drivers, the positive OSA screening yields were 15.7% and 16.9%, respectively. Using both criteria produced an overall positive OSA screen yield of 20.1%. Positive predictive values for applying both guidelines ranged from 72.7% to 95.5%. CONCLUSIONS: The combined use of the 2016 FMCSA and 2006 JTF OSA screening criteria in series has a higher screening yield than using either guideline individually.


Subject(s)
Automobile Driving , Sleep Apnea, Obstructive , Adult , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Sleep Apnea, Obstructive/diagnosis
18.
Am J Prev Med ; 58(1): 79-88, 2020 01.
Article in English | MEDLINE | ID: mdl-31806270

ABSTRACT

INTRODUCTION: Harnessing engagement in online searching and social media may provide complementary information for monitoring alcohol use, informing prevention and policy evaluation, and extending knowledge available from national surveys. METHODS: Relative search volumes for 7 alcohol-related keywords were estimated from Google Trends (data, 2014-2017), and the proportion of alcohol use-related Twitter posts (data, 2014-2015) was estimated using natural language processing. Searching/posting measures were created for all 50 U.S. states plus Washington, D.C. Survey reports of alcohol use and summaries of state alcohol policies were obtained from the Behavioral Risk Factor Surveillance System (data, 2014-2016) and the Alcohol Policy Scale. In 2018-2019, associations among searching/posting measures and same state/year Behavioral Risk Factor Surveillance System reports of recent (past-30-day) alcohol use and maximum number of drinks consumed on an occasion were estimated using logistic and linear regression, adjusting for sociodemographics and Internet use, with moderation tested in regressions that included interactions of select searching/posting measures and the Alcohol Policy Scale. RESULTS: Recent alcohol use was reported by 52.93% of 1,297,168 Behavioral Risk Factor Surveillance System respondents, which was associated with all state-level searching/posting measures in unadjusted and adjusted models (p<0.0001). Among drinkers, most searching/posting measures were associated with maximum number of drinks consumed (p<0.0001). Associations varied with exposure to high versus low levels of state policy controls on alcohol. CONCLUSIONS: Strong associations were found among individual alcohol use and state-level alcohol-related searching/posting measures, which were moderated by the strength of state alcohol policies. Findings support using novel personally generated data to monitor alcohol use and possibly evaluate effects of alcohol control policies.


Subject(s)
Alcohol Drinking/epidemiology , Information Seeking Behavior , Risk Factors , Social Media/statistics & numerical data , State Government , Alcohol Drinking/prevention & control , Behavioral Risk Factor Surveillance System , District of Columbia , Female , Government Regulation , Humans , Male , Middle Aged , Public Policy , United States/epidemiology
19.
PLoS One ; 14(12): e0226637, 2019.
Article in English | MEDLINE | ID: mdl-31881052

ABSTRACT

BACKGROUND: Although studies reported increased cardiovascular (CV) risks in patients treated with macrolides, the risks remain controversial among clarithromycin (CLR) users. We aimed to summarize the association between CLR use and the risks of mortality and CV events. METHODS: We searched PubMed, EMBASE, Web of Science, and the Cochrane Library for randomized controlled trials (RCTs) and observational studies with population exposed to CLR published until December 31st, 2018. These studies reported either all-cause mortality (primary outcome) or CV adverse events (secondary outcomes) based on multivariate models. Effect measures were synthesized by study design and follow-up duration (long-term, ≥ 1 year; short-term, ≤ 3 months; and immediate, ≤ 2 weeks). This study has been registered on PROSPERO (ID: CRD42018089605). RESULTS: This meta-analysis included 13 studies (3 RCTs and 10 observational studies) and 8,351,815 subjects (1,124,672 cases and 7,227,143 controls). Overall, CLR use was not associated with increased long-term all-cause mortality (pooled rate ratio RR = 1.09, 95% CI = 0.91-1.32), either among patients with or without comorbidities of cardiovascular diseases. Comparing CLR users to placebo, there is no additional risks of cardiac mortality (pooled RR = 1.03, 95% CI = 0.53-2.01), acute myocardial infarction (pooled RR = 1.29, 95% CI = 0.98-1.68), and arrhythmia (pooled RR = 0.90, 95% CI = 0.62-1.32). CONCLUSIONS: Our findings suggested no significant association between CLR use and subsequent long-term all-cause mortality, regardless having comorbidity of cardiovascular diseases or not. Further RCTs investigating the short-term CV risks of CLR use compared to alternative antibiotics are warranted, particularly in high-risk populations.


Subject(s)
Anti-Bacterial Agents/adverse effects , Cardiovascular Diseases/chemically induced , Clarithromycin/adverse effects , Arrhythmias, Cardiac/chemically induced , Arrhythmias, Cardiac/epidemiology , Cardiovascular Diseases/epidemiology , Cause of Death , Humans , Myocardial Infarction/chemically induced , Myocardial Infarction/epidemiology , Risk Factors
20.
Nat Commun ; 10(1): 4609, 2019 10 10.
Article in English | MEDLINE | ID: mdl-31601815

ABSTRACT

Constructing two-dimensional (2D) polymers with complex tessellation patterns via synthetic chemistry makes a significant contribution not only to the understanding of the emergence of complex hierarchical systems in living organisms, but also to the fabrication of advanced hierarchical materials. However, to achieve such tasks is a great challenge. In this communication we report a facile and general approach to tessellate 2D covalent organic frameworks (COFs) by three or four geometric shapes/sizes, which affords 2D COFs bearing three or four different kinds of pores and increases structural complexity in tessellations of 2D polymers to a much higher level. The complex tessellation patterns of the COFs are elucidated by powder X-ray diffraction studies, theoretical simulations and high-resolution TEM.

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