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1.
J Org Chem ; 89(10): 6749-6758, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38688007

RESUMO

Disclosed herein is a rhodium(III)-catalyzed direct heteroarylation reaction between unactivated aliphatic C(sp3)-H bonds in 2-alkylpyridines and heteroaryl organoboron reagents. This catalytic protocol is compatible with various heterocyclic boronates containing ortho- and meta-pyridine, pyrazoles, furan, and quinoline with strong coordination capability. The achievement of this methodology provides an efficient route to build new C(sp3)-heteroaryl bonds.

2.
Org Biomol Chem ; 21(25): 5288-5296, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37318055

RESUMO

A catalytic protocol for the Cp*RhIII-promoted C6-selective N-heteroarylation of 2-pyridones with N-heterocyclic boronates has been successfully developed utilizing a removable pyridine auxiliary. This system features high efficiency with mild conditions and also tolerates ortho- and meta-substituted pyridines, pyrazoles, pyrimidine, non-substituted quinolines, thiophene and furan well. The easy synthetic approach could potentially be applied to construct heterocyclic drug molecules bearing 2-pyridone-heteroaryl motifs.

3.
Angew Chem Int Ed Engl ; 62(11): e202216950, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36625196

RESUMO

To conquer the bottleneck of sluggish kinetics in cathodic oxygen reduction reaction (ORR) of metal-air batteries, catalysts with dual-active centers have stood out. Here, a "pre-division metal clusters" strategy is firstly conceived to fabricate a N,S-dual doped honeycomb-like carbon matrix inlaid with CoN4 sites and wrapped Co2 P nanoclusters as dual-active centers (Co2 P/CoN4 @NSC-500). A crystalline {CoII 2 } coordination cluster divided by periphery second organic layers is well-designed to realize delocalized dispersion before calcination. The optimal Co2 P/CoN4 @NSC-500 executes excellent 4e- ORR activity surpassing the benchmark Pt/C. Theoretical calculation results reveal that the CoN4 sites and Co2 P nanoclusters can synergistically quicken the formation of *OOH on Co sites. The rechargeable Zn-air battery (ZAB) assembled by Co2 P/CoN4 @NSC-500 delivers ultralong cycling stability over 1742 hours (3484 cycles) under 5 mA cm-2 and can light up a 2.4 V LED bulb for ≈264 hours, evidencing the promising practical application potentials in portable devices.

4.
Org Biomol Chem ; 20(3): 686-693, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34951443

RESUMO

An efficient RhIII-catalyzed strategy for constructing aryl-heteroaryl derivatives with removable ketoxime ether auxiliaries via direct C-H heteroarylation based on arenes and heteroaromatic boronates has been disclosed. This protocol could tolerate various pyridine, pyrimidine, pyrazole, thiophene, and furan heteroaromatic boronates well, providing the desired products with high reactivities and excellent regioselectivity. The easy synthetic accessibility may offer potential for application in the synthesis of heterocyclic drug molecules containing aryl-heteroaryl motifs.

5.
Inorg Chem ; 60(2): 671-681, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33395274

RESUMO

Luminescent metal-organic frameworks (LMOFs) as sensors showing highly efficient detection toward toxic heavy-metal ions are in high demand for human health and environmental protection. A novel nanocage-based N-rich LMOF (LCU-103) has been constructed and characterized. It is a 2-fold interpenetrating structure built from N-rich {Zn6(dttz)4} nanocages extended by N-donor ligand Hdpa [H3dttz = 4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole; Hdpa = 4,4'-dipyridylamine]. Notably, LCU-103 contains abundant N functional sites anchoring on both the windows of nanocages and the inner channels of the framework that can interact with metal ions and then recognize them. As a result, it can serve as a luminescent sensing material for detecting trace amounts of Fe3+ and Cu2+ ions with low limits of detection (LODs) of 1.45 and 1.66 µM, respectively, through a luminescent quenching mechanism. Meanwhile, LCU-103 as a LMOF sensor exhibits several advantages such as high sensitivity, appropriate selectivity (for Fe3+ in H2O), recycling stability, and fast response times in N,N-dimethylformamide. Moreover, LCU-103 also displays good luminescent quenching activity toward Fe3+ in H2O and a simulated 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid biological system with low LODs of 1.51 and 1.52 µM, respectively. LCU-103 test papers were further prepared to offer easy and real-time detection of Fe3+ and Cu2+ ions. Importantly, when density functional theory calculations and multiple experimental evidence, including X-ray photoelectron spectroscopy, UV-vis absorption, luminescence decay lifetimes, and quantum efficiencies, are combined, a preferred N-donor site and possible weak interaction sensing mechanism is also proposed to elucidate the quenching effect.

6.
Fish Shellfish Immunol ; 81: 368-373, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30031065

RESUMO

The antimicrobial peptide (AMP) Pc-pis, a member of Piscidin family from fish with cationic amphipathic structure, has potent, broad-spectrum antimicrobial activity against bacteria, fungi and parasite, and lower hemolytic activity. Here, we reported that Pc-pis had antitumor activity. Pc-pis killed tumor cells including HeLa cells. Previously, it is reported that AMPs bind to the membrane of bacteria to generate the pores to lyse the target cells, and similarly, the cancer cell incorporate phosphatidyl-serine on the outer leaflet of plasma membrane so that amphipathic AMPs can bind to the membrane to kill it. Our data supported that notion because suitable size osmo-protectant PEG4000 prevented HeLa cells from death induced by Pc-pis. Additionally, Fusion protein GFP-Pc-pis accumulated mainly at the nuclear membranes of HeLa cells and positive net charge in modified Pc-pis intensified but negative net charges eliminated this effect. Thus, positively charged residues were important for its affinity to the membrane. Our work will lay the groundwork of the development of Pc-pis antitumor activity.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/farmacologia , Proteínas de Peixes/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Peixes/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/farmacologia , Células HeLa , Humanos , Membrana Nuclear/metabolismo , Perciformes , Proteínas Recombinantes de Fusão/farmacologia
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 841-5, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-26117908

RESUMO

In order to miniaturize an infrared spectrometer, we analyze the current optical design of miniature spectrometers and propose a method for designing a miniature infrared gratings spectrometer based on planar waveguide. Common miniature spectrometer uses miniature optical elements to reduce the size of system, which also shrinks the effective aperture. So the performance of spectrometer has dropped. Miniaturization principle of planar waveguide spectrometer is different from the principle of common miniature spectrometer. In planar waveguide spectrometer, the propagation of light is limited in a thin planar waveguide, which looks like the whole optical system is squashed flat. In the direction parallel to the planar waveguide, the light through the slit is collimated, dispersed and focused. And a spectral image is formed in the detector plane. This propagation of light is similar to the light in common miniature spectrometer. In the direction perpendicular to the planar waveguide, light is multiple reflected by the upper and lower surfaces of the planar waveguide and propagates in the waveguide. So the size of corresponding optical element could be very small in the vertical direction, which can reduce the size of the optical system. And the performance of the spectrometer is still good. The design method of the planar waveguide spectrometer can be separated into two parts, Czerny-Turner structure design and planar waveguide structure design. First, by using aberration theory an aberration-corrected (spherical aberration, coma, focal curve) Czerny-Turner structure is obtained. The operation wavelength range and spectral resolution are also fixed. Then, by using geometrical optics theory a planar waveguide structure is designed for reducing the system size and correcting the astigmatism. The planar waveguide structure includes a planar waveguide and two cylindrical lenses. Finally, they are modeled together in optical design software and are optimized as a whole. An infrared planar waveguide spectrometer is designed using this method. The operation wavelength range is 8 - 12 µm, the numerical aperture is 0.22, and the linear array detector contains 64 elements. By using Zemax software, the design is optimized and analyzed. The results indicate that the size of the optical system is 130 mm x 125 mm x 20 mm and the spectral resolution of spectrometer is 80 nm, which satisfy the requirements of design index. Thus it is this method that can be used for designing a miniature spectrometer without movable parts and sizes in the range of several cubic centimeters.

8.
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(1): 242-249, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38387929

RESUMO

OBJECTIVE: To establish a graded method to avoid mean fluorescence intensity (MFI) threshold of HLA Class I antibodies corresponding antigen, and the HLAMatchmaker program has been used to select the minimum mismatch value of donor-patient epitopes. Evaluate the application value of combining both methods in selecting HLA compatible platelets (PTL) for patients with immune platelet transfusion failure (IPTR) in improving platelet the corrected count increment (CCI). METHODS: A total 7 807 PLT cross-matching compatible were performed by the solid-phase red cell adherence (SPRCA) method for 51 IPTR patients. The Luminex single antigen flow cytometry was used to detect HLA Class I antibodies in patients, and detected the MFI value for different specificity antigens of HLA Class I antibodies, was graded into strong positive group (MFI>4 000, level 1), medium positive group (1 000< MFI≤4 000, 2), weak positive group (500< MFI≤1 000, 3), and one negative control group (MFI≤500). The results of 7 807 SPRCA their negative/positive reaction wells were enrolled and statistically analyzed in different grades and the four groups, the statistical differences between the four groups were compared. Multiple applications for the select HLA Class I compatible donor events were made for patients in two cases, and HLAMatchmaker program was used to calculate the number of HLA Class I epitopes mismatches between the donors and patients. The donor with the minimum number of epitopes mismatches was selected, while avoiding the corresponding antigens of HLA Class I antibodies in levels 1 and 2, the provision of HLA compatible platelets for IPTR. After the transfusions, the CCI value of the platelet transfusion efficacy evaluation index was calculated, and the clinical evaluation of the transfusion effect was obtained through statistical analysis. RESULTS: There were statistically significant differences in the positive results of SPRCA immunoassay among the strong positive group, medium positive group, and weak positive group of 51 IPTR patients with different specific of HLA -I class antibodies and corresponding antigens(all P <0.001). The positive results showed a range from high to low, with strong positive group>medium positive group>weak positive group. There were a statistical difference among between the strongly positive or moderately positive groups and the negative control group(P <0.001). There was no statistical difference between the weakly positive group and the negative control group(P >0.05). The strong positive group was set as the corresponding specific HLA Class I site corresponding antigen grade 1 avoidance threshold, the medium positive group as the grade 2 avoidance thresholds, and the weak positive group as the grade 3 avoidance threshold. In the case of donor platelet shortage, it is not necessary to avoid the weak positive group. Avoiding the strategy of donor antigens and HLAMatchmaker program scores ≤7 corresponding to HLA Class I antibodies of levels 1 and 2, with CCI values>4.5×109/L within 24 hours, can obtain effective clinical platelet transfusion conclusions. CONCLUSION: When selecting HLA Class I compatible donors for IPTR patients, the grading avoids HLA Class I antibodies corresponding to donor antigens, and the donor selection strategy with the minimum scores of HLAMatchmaker program is comprehensively selected. The negative result confirmed by platelet cross-matching experiments has certain practical application value for improving platelet count in IPTR patients.


Assuntos
Plaquetas , Transfusão de Plaquetas , Humanos , Transfusão de Sangue , Epitopos , Antígenos de Histocompatibilidade Classe I , Teste de Histocompatibilidade , Antígenos HLA , Isoanticorpos , Tipagem e Reações Cruzadas Sanguíneas
10.
HLA ; 102(6): 750-752, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37771212

RESUMO

HLA-A*26:206:02N differs from A*26:01:01:01 by a single nucleotide exchange in exon 3.


Assuntos
Genômica , Hepatite B , Humanos , Alelos , Éxons/genética , Antígenos HLA-A/genética , Hepatite B/genética , Sequenciamento de Nucleotídeos em Larga Escala
11.
ACS Appl Mater Interfaces ; 15(2): 2940-2950, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36598797

RESUMO

The cathodic product Li2CO3, due to its high decomposition potential, has hindered the practical application of rechargeable Li-CO2/O2 batteries. To overcome this bottleneck, a Pt/FeNC cathodic catalyst is fabricated by dispersing Pt nanoparticles (NPs) with a uniform size of 2.4 nm and 8.3 wt % loading amount into a porous microcube FeNC support for high-performance rechargeable Li-CO2/O2 batteries. The FeNC matrix is composed of numerous two-dimensional (2D) carbon nanosheets, which is derived from an Fe-doping zinc metal-organic framework (Zn-MOF). Importantly, using Pt/FeNC as the cathodic catalyst, the Li-CO2/O2 (VCO2/VO2 = 4:1) battery displays the lowest overpotential of 0.54 V and a long-term stability of 142 cycles, which is superior to batteries with FeNC (1.67 V, 47 cycles) and NC (1.87 V, 23 cycles) catalysts. The FeNC matrix and Pt NPs can exert a synergetic effect to decrease the decomposition potential of Li2CO3 and thus enhance the battery performance. In situ Fourier transform infrared (FTIR) spectroscopy further confirms that Li2CO3 can be completely decomposed under a low potential of 3.3 V using the Pt/FeNC catalyst. Impressively, Li2CO3 exhibits a film structure on the surface of the Pt/FeNC catalysts by scanning electron microscopy (SEM), and its size can be limited by the confined space between the carbon sheets in Pt/FeNC, which enlarges the better contacting interface. In addition, density functional theory (DFT) calculations reveal that the Pt and FeNC catalysts show a higher adsorption energy for Li2CO3 and Li2CO4 intermediates compared to the NC catalyst, and the possible discharge pathways are deeply investigated. The synergetic effect between the FeNC support and Pt active sites makes the Li-CO2/O2 battery achieve optimal performance.

12.
Zhonghua Nei Ke Za Zhi ; 51(11): 885-8, 2012 Nov.
Artigo em Zh | MEDLINE | ID: mdl-23291028

RESUMO

OBJECTIVE: To study the regional cerebral glucose utilization with (18)F-fluorodeoxyglucose (FDG) PET and to investigate the correlation between cerebral glucose metabolism and the clinical characteristic of progressive supranuclear palsy (PSP). METHODS: A total of 13 patients with PSP and 30 matched healthy controls were performed (18)F-FDG PET imaging at rest state. Visual inspection and statistical parametric mapping (SPM) were used to investigate regional cerebral metabolic rate of glucose (rCMRglc). RESULTS: Based on the visual inspection, PET imaging in the PSP patients showed that the focal hypometabolic areas mainly included the bilateral frontal cortex, midbrain and subcortical structures. Compared to the controls, voxel-based analysis showed that the regional glucose metabolism decreased in bilateral superior, middle frontal gyrus, cingulate gyrus, midbrain and subcortical structures including basal ganglion and thalamus, which were consisted with the clinical characteristics, such as vertical gaze palsy, pseudobulbar palsy, postural instability, axial rigidity, dementia and so on. CONCLUSION: (18)F-FDG PET imaging is helpful for the early diagnosis of PSP.


Assuntos
Encéfalo/metabolismo , Glucose/metabolismo , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/metabolismo , Idoso , Estudos de Casos e Controles , Demência/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 147-51, 2012 Jan.
Artigo em Zh | MEDLINE | ID: mdl-22497147

RESUMO

The molecular structure and spectral properties of a novel acylhydrazone ligands 2-hydroxy-naphthaldehyde-5-chloro-salicyloylhydrazone (H3L) and its Sn metal complexes [(n-Bu2)Sn(HL)] in solution, crystal and thin films were investigated by using steady state and time resolved fluorescence spectrum. The experimental results show that for H3L, compared with it in solution, the fluorescence intensity is enhanced as it is crystal and thin films, the fluorescence peak is red-shift, and the excited state lifetime is longer. The transition energies of the unimolecule is 240.2 kJ x mol(-1). For (n-Bu2)Sn(HL), the fluorescence intensity is stronger as it is crystal than it is in solution and the fluorescence peak is red-shilft, the excited state lifetime is longer. The fluorescence is quenched as it is in thin films. The transition energies of the unimolecule is 230.4 kJ x mol(-1). The fluorescence intensity of (n-Bu2)Sn(HL) is four times higher than the H3L. The excited state lifetime of (n-Bu2) Sn(HL) is longer than H2L too. In theory, these phenomena could be explained by that with the increase of the conjugated system and the rigid construction, the fluorescence intensity is stronger and the excited state lifetime is longer.

14.
World J Clin Cases ; 10(10): 3069-3077, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35647121

RESUMO

BACKGROUND: Elderly patients tend to have poor self-efficacy and poor confidence in postoperative rehabilitation for hip fractures, and are prone to negative emotions, which affect treatment compliance. AIM: To evaluate the effects of evidence-based intervention on postoperative fear, compliance, and self-efficacy in elderly patients with hip fractures. METHODS: A total of 120 patients with hip fracture surgically treated from June 2018 to June 2020 at the orthopedic department of our hospital were selected and divided into intervention and routine groups (n = 60 each) according to different nursing methods. The basic rehabilitation methods of the two groups were consistent, but patients in the intervention group received evidence-based nursing interventions at the same time. Differences between groups in the scores of motion phobia, pain fear, rehabilitation training compliance, self-efficacy, nursing satisfaction, and hip joint function were compared before and after the intervention. RESULTS: Before the intervention, there were no statistically significant differences in motion phobia and pain fear scores between the groups (all P > 0.05). However, motion phobia scores at 1 wk after intervention initiation (P < 0.05), and pain fear scores at 1 wk and 2 wk after intervention initiation (all P < 0.05), were significantly lower in the intervention group than in the routine group. On the first day of intervention, there was no significant difference in rehabilitation treatment compliance between the groups (P > 0.05); however, at 2 wk after intervention initiation, rehabilitation compliance was significantly better in the intervention group than in the routine group (P < 0.05). Before the intervention, there were no statistically significant differences in the scores for the two self-efficacy dimensions (overcoming difficulties and rehabilitation exercise self-efficacy) and the total self-efficacy score between the groups (all P > 0.05). After 2 wk of intervention, the scores for these two dimensions of self-efficacy and the total self-efficacy score were significantly higher in the intervention group than in the routine group (all P < 0.05). At 3 and 6 mo after surgery, hip function as evaluated by the Harris hip score, was significantly better in the intervention group than in the routine group (P < 0.05). Additionally, overall nursing satisfaction was significantly higher in the intervention group than in the routine group (P < 0.05). CONCLUSION: Evidence-based nursing intervention can alleviate fear of postoperative rehabilitation in elderly patients who underwent hip fracture surgery, and improve rehabilitation treatment compliance and patient self-efficacy, which promote hip function recovery.

15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(3): 884-889, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35680822

RESUMO

OBJECTIVE: To analyze the molecular polymorphisms of CD36 among 58 blood donors with CD36 deficiency and compare with CD36 positive controls. METHODS: A total of 58 donors with CD36 deficiency during a screening conducted in the laboratory from September 2019 to December 2020 were enrolled as the test group, including 39 males and 19 females, while 120 platelet donors with CD36 positive were randomly selected as the controls, including 76 males and 44 females. All of the subjects were Han nationality. The PCR-SBT method was used to detect coding region of CD36 gene, and molecular mutations were compared with those CD36 positive controls. RESULTS: Among the 58 donors with CD36 deficiency, mutations appears in 32 individuals. The detection rate for type I was 71.43% (5/7), and type II was 51.92% (27/52), while among the 120 controls, mutations appears in 12 donors (10%). In the CD36 antigen-deficient donors, 16 variations were found, in which 329-330 del AC with the highest frequency accounted for 20.69%, followed by 1228-1239 del ATTGTGCCTATT(15.52%) and 1156 C>T(10.34%). Two variations, 198-205 del GATCTTTG and 220 C>T, led to premature termination of translation; four mutations, 329-330 del AC, 560 ins T, 1011-1049 39bp dupl and 1343-1344 ins TCTT, caused translation frame shift; 1228-1239 del ATTGTGCCTATT led to deletion of four amino acids (Ile-Val-Pro-Ile) at sites 410-413 of the peptide chain. The 1140 T>A and 1275 G>A were synonymous mutations, and the other 7 mutations resulted in the substitution of single nucleotide. The platelet expression in the donors of CD36 positive with 329-330 del AC or 1228-1239 del ATTGTGCCTATT mutation (heterozygote) was lower than those CD36 positive individuals without mutations (homozygote). CONCLUSION: Multiple gene mutations in the CD36 coding region may cause CD36 deficiency, and the heterozygous individuals with mutations may lead to CD36 antigen reduction or deletion. Mutation is not detected in 44.83% of CD36 deficient individuals, there may be some other reasons for the CD36 antigen deficiency.


Assuntos
Transtornos Plaquetários , Antígenos CD36 , Doadores de Sangue , Transtornos Plaquetários/genética , Transtornos Plaquetários/metabolismo , Plaquetas/química , Plaquetas/metabolismo , Antígenos CD36/análise , Antígenos CD36/genética , Antígenos CD36/metabolismo , Feminino , Doenças Genéticas Inatas , Humanos , Masculino
16.
Org Lett ; 24(31): 5704-5709, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35912970

RESUMO

A RhIII-catalyzed C(sp2)-H N-heteroarylation and esterification cascade of aryl carboxylic acids with N-heteroaromatic boronates and 1,2-dichloroethane in a one-pot synthesis has been disclosed. The strong coordinating ability of ortho- and meta-substituted pyridine boronates and pyrazoles as well as unsubstituted pyrimidine allows them to serve as the coupling partners. This protocol allows late-stage modification of the key precursor of roflumilast and compounds of pharmaceutical interest, which highlights the potential application of this synthetic method.


Assuntos
Ácidos Carboxílicos , Catálise , Esterificação , Dicloretos de Etileno , Indicadores e Reagentes
17.
Org Lett ; 24(48): 8747-8752, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36450131

RESUMO

A carboxylate-assisted iridium(III)-catalyzed regioselective C(sp2)-H heteroarylation/esterification reaction of acrylic acid is disclosed herein for the first time. This catalytic protocol tolerates various α-substituted, ß-substituted, and α, ß-disubstituted acrylic acids as well as heteroaromatic boronates well. The resulting 3,4-dihydro-2H-pyran-6-carboxylic acid derivative 3r highlighted the AIE-active luminophore with multiple emission signal properties and a high quantum yield of 28%, exhibiting the potential application of this methodology for the synthesis of nitrogen-containing organic functional materials.

18.
Dalton Trans ; 51(20): 7817-7827, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35532008

RESUMO

High-performance lithium ion batteries (LIBs) juggling high reversible capacity, excellent rate capability and ultralong cycle stability are urgently needed for all electronic devices. Here we report employing a vesicle-like porous N-doped carbon material (abbr. N/C-900) as a highly active anode for LIBs to balance high capacity, high rate and long life. The N/C-900 material was fabricated by pyrolysis of a designed crystal MOF LCU-104, which exhibits a graceful two-fold interpenetrating structural feature of N-rich nanocages {Zn6(dttz)4} linked through an N-donor ligand bpp (H3dttz = 4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole, bpp = 1,3-bis(4-pyridyl)propane). The features of LCU-104 combine high N content (35.1%), interpenetration, and explosive characteristics, which endow the derived N/C material with optimized N-doping for tuning its chemical and electronic structure, a suitably thicker wall to enhance its stability, and a vesicle-like structure to improve its porosity. As an anode material for LIBs, N/C-900 delivers a highly reversible capacity of ca. 734 mA h g-1 at a large current density of 1 A g-1 until the 2000th cycle, revealing its ultralong cycle stability and excellent rate capability. The unique structure and preferential interaction between abundant pyridinic N active sites and Li atoms are responsible for the improved excellent lithium storage capacity and durability performances of the anode according to analysis of the results of computational modeling.

19.
HLA ; 98(5): 488-490, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34390544

RESUMO

The HLA-DRB3*02:02:19 allele differs from DRB3*02:02:01:02 by a single nucleotide change in exon 2.


Assuntos
Nucleotídeos , Alelos , Éxons/genética , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB3/genética , Teste de Histocompatibilidade , Humanos
20.
Org Lett ; 23(3): 656-662, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33443430

RESUMO

RhIII-catalyzed sp2 C-H cross-coupling of acrylamides with organoboron reactants has been accomplished using a commercially available N-2,6-difluoroaryl acrylamide auxiliary. A broad range of aryl and vinyl boronates as well as a variety of heterocyclic boronates with strong coordinating ability can serve as the coupling partners. This transformation proceeds under moderate reaction conditions with excellent functional group tolerance and high regioselectivity.

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