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11.
Zhiwei Qiao Lifeng Li Shuhua Li Hong Liang Jian Zhou Randall Q. Snurr 《American Institute of Chemical Engineers》2021,67(10):e17352
Computational screening was employed to calculate the enantioseparation capabilities of 45 functionalized homochiral metal–organic frameworks (FHMOFs), and machine learning (ML) and molecular fingerprint (MF) techniques were used to find new FHMOFs with high performance. With increasing temperature, the enantioselectivities for (R,S)-1,3-dimethyl-1,2-propadiene are improved. The “glove effect” in the chiral pockets was proposed to explain the correlations between the steric effect of functional groups and performance of FHMOFs. Moreover, the neighborhood component analysis and RDKit/MACCS MFs show the highest predictive effect on enantioselectivities among the four ML classification algorithms with nine MFs that were tested. Based on the importance of MF, 85 new FHMOFs were designed, and a newly designed FHMOF, NO2-NHOH-FHMOF, with high similarity to the optimal MFs achieved improved chiral separation performance, with enantioselectivities of 85%. The design principles and new chiral pockets obtained by ML and MFs could facilitate the development of new materials for chiral separation. 相似文献
12.
针对CAGAN(Conditional Analogy GAN)换衣后效果模糊,在目标衣服与原始衣服长短不一致时效果一般,相对目标衣服保留过少的细节等问题做了相关研究并对CAGAN进行了改进,提出了新的虚拟试衣方式。经过改进的CAGAN生成一个粗糙的结果,由该结果得到目标衣服穿在模特身上改变形状后的mask,接下来利用mask对目标衣服进行变形,综合变形的衣服和第一步的结果便得到最终的试衣图像。实验结果表明,该方法解决了前面存在的问题,而且取得了非常好的效果。 相似文献
13.
建立了一种快速、灵敏测定药物中盐酸美西律的双波长分光光度法。在弱碱性溶液中,虎红与盐酸美西律反应生成离子缔合物,使溶液发生褪色现象,光谱曲线上呈现2个较强的负吸收峰,它们分别位于472和560 nm,在此2个波长处,盐酸美西律的线性范围为0.04~2.6 mg/L,表观摩尔吸光系数(κ)分别为5.87×104(472 nm)和3.59×104 L/(mol·cm)(560 nm),检出限为0.033(472 nm)和0.035 mg/L(560 nm)。用双波长法测定时,其表观摩尔吸光系数(κ)达9.46×104 L/(mol·cm),检出限为0.017 mg/L。双波长法用于盐酸美西律药片测定,加标回收率为97.7%~103%,相对标准偏差(RSD)为2.2%~2.6%。 相似文献
14.
While the challenges associated with the stability of metal halide perovskites are well known and intensely studied, variability in electronic properties represents an equally significant, yet seldom studied, challenge that could potentially slow or inhibit the commercial viability of these systems. In this work, the contactless characterization technique time-resolved microwave conductivity (TRMC) is used to quantify the variability in electronic properties of the prototypical perovskite, methylammonium lead iodide (MAPbI3) both between different samples, and at different locations within the same sample. Using scanning electron microscopy (SEM) and a quasi-automated image-analysis strategy, it is possible to evaluate the metrics of heterogeneity in surface microstructure and correlate them with the electronic properties as obtained by TRMC. Substantial intra-sample and inter-sample variation is observed in the mobility-yield product in samples prepared following differing protocols, and in samples prepared following identical protocols. 相似文献
15.
从某商住综合型小区项目着手,运用关键路径、甘特图、鱼骨图等方法进行研究,对该项目前期管理决策筹备、施工监管、竣工验收3个阶段的特点和问题进行分析,总结出建设项目的前期管理形成了若干闭环管理系统,通过构成连续、封闭回路的各管理任务,对各项建设内容进行多角度管理.采用制度管理、标准化管理、计划管理、目标与考核管理等措施,制订前期管理的优化方案.对优化后方案的模拟实施进行评估可得出,优化前期管理可缩短项目整体工期. 相似文献
16.
Yu-Hung Lee Ching-Fang Yu Ying-Chieh Yang Ji-Hong Hong Chi-Shiun Chiang 《International journal of molecular sciences》2021,22(4)
The low overall survival rate of patients with pancreatic cancer has driven research to seek a new therapeutic protocol. Radiotherapy (RT) is frequently an option in the neoadjuvant or palliative settings for pancreatic cancer treatment. This study explored the effect of RT protocols on the tumor microenvironment (TME) and their consequent impact on anti-programmed cell death ligand-1 (PD-L1) therapy. Using a murine orthotopic pancreatic tumor model, UN-KC-6141, RT-disturbed TME was examined by immunohistochemical staining. The results showed that ablative RT is more effective than fractionated RT at recruiting T cells. On the other hand, fractionated RT induces more myeloid-derived suppressor cell infiltration than ablative RT. The RT-disturbed TME presents a higher perfusion rate per vessel. The increase in vessel perfusion is associated with a higher amount of anti-PD-L1 antibody being delivered to the tumor. Animal survival is increased by anti-PD-L1 therapy after ablative RT, with 67% of treated animals surviving more than 30 days after tumor inoculation compared to a median survival time of 16.5 days for the control group. Splenocytes isolated from surviving animals were specifically cytotoxic for UN-KC-6141 cells. We conclude that the ablative RT-induced TME is more suited than conventional RT-induced TME to combination therapy with immune checkpoint blockade. 相似文献
17.
Siyao Li Shoulei Xu Xiangyu Wang Daini Wang Bernard A. Goodman Xing Hong Wen Deng 《Ceramics International》2021,47(3):3346-3353
Cubic zirconia single crystals stabilized with yttria and doped with Gd2O3 (0.10–5.00 mol%) were prepared by the optical floating zone method, and characterized by a combination of X-ray diffraction (XRD), and Raman, electron paramagnetic resonance (EPR), ultraviolet–visible (UV–Vis), photoluminescence excitation (PLE) and photoluminescence (PL) spectroscopic techniques. XRD and Raman spectroscopy showed that the crystal samples were all in the cubic phase, whereas the ceramic sample consisted of a mixture of monoclinic and cubic phases. The absorption spectrum showed four peaks at 245, 273, 308, and 314 nm in the ultraviolet region, and the optical band gap differed between samples with ≤3.00 mol% and those with >3.00 mol% Gd2O3. The emission spectrum showed a weak peak at 308 nm and a strong peak at 314 nm, which are attributed to the 6P5/2 → 8S7/2 and 6P7/2 → 8S7/2 transitions of Gd3+, respectively. The intensities of the peaks in the excitation and emission spectra increased with Gd3+ concentration, reached a maximum at 2.00 mol%, then decreased with higher concentrations. This quenching is considered to be the result of the electric dipole-dipole interactions, and this interpretation is supported by the Gd3+ EPR spectra, which showed progressive broadening with increasing Gd3+ concentration throughout the concentration range investigated. 相似文献
18.
Prof. Tsung-Shing Andrew Wang Ruo-Yu Wu Yu Hong Dr. Zhe-Chong Wang Dr. Tsung-Lin Li Dr. Jiun-Jie Shie Prof. Cheng-Chih Hsu 《Chembiochem : a European journal of chemical biology》2021,22(14):2415-2419
Secondary metabolites are structurally diverse natural products (NPs) and have been widely used for medical applications. Developing new tools to enrich NPs can be a promising solution to isolate novel NPs from the native and complex samples. Here, we developed native and deuterated chemoselective labeling probes to target phenol-containing glycopeptides by the ene-type labeling used in proteomic research. The clickable azido-linker was included for further biotin functionalization to facilitate the enrichment of labeled substrates. Afterward, our chemoselective method, in conjunction with LC-MS and MSn analysis, was demonstrated in bacterial cultures. A vancomycin-related phenol-containing glycopeptide was labeled and characterized by our labeling strategy, showing its potential in glycopeptide discovery in complex environments. 相似文献
19.
Patil Rupesh C. Jagdale Ashutosh A. Patil Uttam P. Ghodake Jeevan S. Mali Sawanta S. Hong Chang K. Patil Suresh S. 《Catalysis Letters》2021,151(12):3617-3631
Catalysis Letters - We converted agro-waste Custard Apple Peels (CAP) to ash via thermal treatment, on which Pd(OAc)2 was immobilized easily that produced a low-cost, highly efficient Pd/CAP-ash... 相似文献
20.
Andrew N. Kuhn Haidong Zhao Uzoma O. Nwabara Xiaofei Lu Mingyan Liu Yung-Tin Pan Wenjin Zhu Paul J. A. Kenis Hong Yang 《Advanced functional materials》2021,31(26):2101668
Copper catalysts are widely studied for the electroreduction of carbon dioxide (CO2) to value-added hydrocarbon products. Controlling the surface composition of copper nanomaterials may provide the electronic and structural properties necessary for carbon-carbon coupling, thus increasing the Faradaic efficiency (FE) towards ethylene and other multi-carbon (C2+) products. Synthesis and catalytic study of silver-coated copper nanoparticles (Cu@Ag NPs) for the reduction of CO2 are presented. Bimetallic CuAg NPs are typically difficult to produce due to the bulk immiscibility between these two metals. Slow injection of the silver precursor, concentrations of organic capping agents, and gas environment proved critical to control the size and metal distribution of the Cu@Ag NPs. The optimized Cu@Ag electrocatalyst exhibited a very low onset cell potential of −2.25 V for ethylene formation, reaching a FE towards C2+ products (FEC2+) of 43% at −2.50 V, which is 1.0 V lower than a reference Cu catalyst to reach a similar FEC2+. The high ethylene formation at low potentials is attributed to enhanced C C coupling on the Ag enriched shell of the Cu@Ag electrocatalysts. This study offers a new catalyst design towards increasing the efficiency for the electroreduction of CO2 to value-added chemicals. 相似文献