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991.
A novel strategy for the construction of many-electron symmetry-adapted wave function is proposed for ab initio valence bond (VB) calculations and is implemented for valence bond self-consistent filed (VBSCF) and breathing orbital valence bond (BOVB) methods with various orbital optimization algorithms. Symmetry-adapted VB functions are constructed by the projection operator of symmetry group. The many-electron symmetry-adapted wave function is expressed in terms of symmetry-adapted VB functions, and thus the VB calculations can be performed with the molecular symmetry restriction. Test results show that molecular symmetry reduces the computational cost of both the iteration numbers and CPU time. Furthermore, excited states with specific symmetry can be conveniently obtained in VB calculations by using symmetry-adapted VB functions. 相似文献
992.
采用毒性小、环境友好的乙二醇甲醚(ethylene glycol monomethyl ether,EGME)与水混合的双溶剂(体积比为1∶1)溶解CsBr,通过提高CsBr的溶解度,减少了后续CsBr的甲醇溶液的旋涂遍数,简化了电池制备流程。通过优化CsBr的甲醇溶液的旋涂遍数发现,在旋涂1遍200 mg·mL-1 CsBr的水/EGME溶液的基础上旋涂2遍15 mg·mL-1 CsBr的甲醇溶液,所制备的CsPb-Br3钙钛矿太阳能电池(perovskite solar cells,PSCs)拥有最佳的性能,实现了1.44 V的开路电压(open-circuit voltage,VOC),6.26mA·cm-2的短路电流密度(short circuit current density,JSC),74.57%的填充因子(fill factor,FF)及最高6.72%的光电转换效率(pho-toelectric conversion efficiency,PCE)。 相似文献
993.
《中国化学快报》2023,34(4):107465
Sodium-ion batteries (SIB) have attracted widespread attention in large-scale energy storage fields owing to the abundant reserve in the earth and similar properties of sodium to lithium. Biomass-based carbon materials with low-cost, controllable structure, simple processing technology, and environmental friendliness tick almost all the right boxes as one of the promising anode materials for SIB. Herein, we present a simple novel strategy involving tea tomenta biomass-derived carbon anode with enhanced interlayer carbon distance (0.44 nm) and high performance, which is constructed by N,P co-doped hard carbon (Tea-1100-NP) derived from tea tomenta. The prepared Tea-1100-NP composite could deliver a high reversible capacity (326.1 mAh/g at 28 mA/g), high initial coulombic efficiency (ICE = 90% at 28 mA/g), stable cycle life (262.4 mAh/g at 280 mA/g for 100 cycles), and superior rate performance (224.5 mAh/g at 1400 mA/g). Experimental results show that the excellent electrochemical performance of Tea-1100-NP due to the high number of active N,P-containing groups, and disordered amorphous structures provide ample active sites and increase the conductivity, meanwhile, large amounts of microporous shorten the Na+ diffusion distance as well as quicken ion transport. This work provides a new type of N,P co-doped high-performance tomenta-derived carbon, which may also greatly promote the commercial application of SIB. 相似文献
994.
《中国化学快报》2023,34(3):107577
Nitric oxide (NO) gas therapy has been regarded as a promising strategy for cancer treatment. However, its therapeutic efficiency is still unsatisfying due to the limitations of monotherapy. Previous preclinical and clinical studies have shown that combination therapy could significantly enhance therapeutic efficiency. Herein, a graphene oxide (GO)-l-arginine (l-Arg, a natural NO donor) hybrid nanogenerator is developed followed by surface functionalization of soybean lecithin (SL) for synergistic enhancement of cancer treatment through photothermal and gas therapy. The resultant GO-Arg-SL nanogenerator not only exhibited good biocompatibility and excellent endocytosis ability, but also exhibited excellent photothermal conversion capability and high sensitivity to release NO within tumor microenvironment via inducible NO synthase (iNOS) catalyzation. Moreover, the produced hyperthermia and intracellular NO could synergistically kill cancer cells both in vitro and in vivo. More importantly, this nanogenerator can efficiently eliminate tumor while inhibiting the tumor recurrence because of the immunogenic cell death (ICD) elicited by NIR laser-triggered hyperthermia and the immune response activation by massive NO generation. We envision that the GO-Arg-SL nanogenerator could provide a potential strategy for synergistic photothermal and gas therapy. 相似文献
995.
996.
《中国化学快报》2023,34(6):107923
The abnormal activation of BRD4 accelerates the progression of acute myeloid leukemia (AML), developing more precise therapeutics to intervene BRD4 promise to be an excellent opportunity to avoid current limitations of chemotherapy in clinic. Herein, a range of small-molecule PROTACs with the privileged 8-methyl-pyrrolo[1,2-a]pyrazin-1(2H)-one scaffold were rationally designed, which harbored different carbon or ethylenedioxy chains to degrade BRD4 mediated by the E3 ubiquitin ligase CRBN. Among them, the most potential B24 exhibited remarkable BRD4 degradation and excellent anti-proliferative activities in MV4-11 cells, with values of DC50 and IC50 for 0.75 nmol/L and 0.4 nmol/L, respectively, which were better than the BRD4 inhibitor (+)-JQ-1. Notably, this compound could time-dependently degrade the target protein in the BRD4-, CRBN-, and proteasome-dependent manner. Besides, B24 dramatically decreased the level of proto-oncogene c-Myc, and induced cell apoptosis by arresting the cell cycle in G0/G1 phase, down-regulating Bcl-2 and up-regulating Bax to amplify apoptotic effectors. This proof-of-concept study also highlighted the feasibility of BRD4-based PROTACs as a more powerful strategy against AML. 相似文献
997.
Developing multiplex sensing technique is of great significance for fast sample analysis. However, the broad emissions of most chemiluminescence(CL) luminophores make the multiplex CL analysis be difficult. In this work, a simple and sensitive CL analytical method has been developed for the simultaneous determination of Tb3+and Eu3+thanking to their narrow band emission. The technique was based on a mixed CL system of periodate(IO4-)-hydrogen peroxide(... 相似文献
998.
《中国化学快报》2023,34(11):108263
The sluggish conversion kinetics and shuttle effect of lithium polysulfides (LiPSs) severely hamper the commercialization of lithium–sulfur batteries. Numerous electrocatalysts have been used to address these issues, amongst which, transition metal dichalcogenides have shown excellent catalytic performance in the study of lithium–sulfur batteries. Note that dichalcogenides in different phases have different catalytic properties, and such catalytic materials in different phases have a prominent impact on the performance of lithium–sulfur batteries. Herein, 1T-phase rich MoSe2 (T-MoSe2) nanosheets are synthesized and used to catalyze the conversion of LiPSs. Compared with the 2H-phase rich MoSe2 (H-MoSe2) nanosheets, the T-MoSe2 nanosheets significantly accelerate the liquid phase transformation of LiPSs and the nucleation process of Li2S. In-situ Raman and X-ray photoelectron spectroscopy (XPS) find that T-MoSe2 effectively captures LiPSs through the formation of Mo-S and Li-Se bonds, and simultaneously achieves fast catalytic conversion of LiPSs. The lithium–sulfur batteries with T-MoSe2 functionalized separators display a fantastic rate performance of 770.1 mAh/g at 3 C and wonderful cycling stability, with a capacity decay rate as low as 0.065% during 400 cycles at 1 C. This work offers a novel perspective for the rational design of selenide electrocatalysts in lithium–sulfur chemistry. 相似文献
999.
《中国化学快报》2023,34(12):108453
A cooperative Pd/Cu-catalyzed three-component cross-coupling reaction of alkynes, B2Pin2 and alkene-tethered aryl halides is reported. This reaction proceeds under mild conditions and shows broad substrate scope, providing a variety of heterocycles containing tetrasubstituted alkenylboronate moieties in synthetically useful yields with excellent chemoselectivity and regioselectivity. This transformation features the catalytic generation of β-borylalkenylcopper intermediates and their use in Pd-catalyzed Heck cyclization/cross-couplings. An enantioselective cascade cyclization/cross-coupling process has also been developed for the synthesis of enantiomerically enriched oxindole bearing a tetrasubstituted alkenylboronate moiety. 相似文献
1000.
Dr. Wenqing Wang Xiao-Hui Ma Min Liu Shuxuan Tang Xuguang Ding Yue Zhao Prof. Yuan-Zhi Tan Prof. Miklos Kertesz Prof. Xinping Wang 《Angewandte Chemie (International ed. in English)》2023,62(8):e202217788
We report on the largest open-shell graphenic bilayer and also the first example of triply negatively charged radical π-dimer. Upon three-electron reduction, bilayer nanographene fragment molecule (C96H24Ar6)2 (Ar=2,6-dimethylphenyl) ( 1 2) was transformed to a triply negatively charged species 1 23.−, which has been characterized by single-crystal X-ray diffraction, electron paramagnetic resonance (EPR) spectroscopy and magnetic properties on a superconducting quantum interference device (SQUID). 1 23.− features a 96-center-3-electron (96c/3e) pancake bond with a doublet ground state, which can be thermally excited to a quartet state. It consists of 34 π-fused rings with 96 conjugated sp2 carbon atoms. Spin frustration is observed with the frustration parameter f>31.8 at low temperatures in 1 23.−, which indicates graphene upon reduction doping may behave as a quantum spin liquid. 相似文献