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Precise Molecular Sieving Architectures with Janus Pathways for Both Polar and Nonpolar Molecules 下载免费PDF全文
Jiangtao Liu Dan Hua Yu Zhang Susilo Japip Tai‐Shung Chung 《Advanced materials (Deerfield Beach, Fla.)》2018,30(11)
Precise molecular sieving architectures with Janus superhighways are constructed via a molecularly engineered interfacial reaction between cyclodextrin (CD) and trimesoyl chloride (TMC). Interestingly, the CD/TMC nanofilms constructed with both hydrophobic inner cavities and hydrophilic channels exhibit exceptionally high permeances for both polar and nonpolar solvents. The precise molecular sieving functions are determined by the type of CD building blocks and the inner cavities of intrinsic 3D hollow bowls. Positron annihilation spectroscopy (PAS) confirms that a larger inner CD cavity tends to generate a larger free volume and higher microporosity. Based on the rejection ratio of various dyes, the estimated molecular weight cutoff of CD/TMC nanofilms follows the trend of α‐CD/TMC (320 Da) <β‐CD/TMC (400 Da) <γ‐CD/TMC (550 Da), which is in strict accordance with the orders of their free volumes measured by PAS and inner cavity sizes of α‐CD <β‐CD <γ‐CD. This kind of novel CD/TMC molecular sieving membrane with intrinsic microporosity containing tunable pore size and sharp pore‐size distribution can effectively discriminate molecules with different 3D sizes. 相似文献
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目的研究使用CMYK四色复制品牌色时品牌色颜色宽容度的评判方法和可复制百分比。方法从ICC色彩管理流程着手,研究色彩转换过程、复制过程及测量仪器之间的色差,结合视觉理论给出评定品牌色复制性颜色宽容度的影响系数及数据。结果品牌色可复制性评判的颜色宽容度为3.5?E_(00),指定ICC Profile转换的品牌色可复制比例分别为65%(CGATS21-CRPC5),74%(CGATS21_CRPC6)和86%(CGATS21_CRPC7))。结论所提出的判定品牌色可复制颜色宽容度方法可以给印刷标准单位用来定量评价品牌色在不同四色印刷条件的可复制百分比。 相似文献
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Chia En Liu Wen Chieh Lan Hao Ting Yu Han Lin Yang I. Tseng Liu Hsiao Ping Hsu Chung Wen Lan 《International Journal of Applied Ceramic Technology》2020,17(1):146-152
Silicon kerf loss during wafer slicing and the broken quartz crucibles after silicon casting are two major solid wastes from photovoltaic (PV) industry. Especially, the recycle of kerf-loss silicon has become an urgent issue because near 100 000 t of solid wastes are generated every year. One of the most meaningful recycle routes of the kerf-loss silicon is to make silicon nitride crucibles to replace the quartz crucibles. In this study, we demonstrated how this is feasible through acid leaching refining, slip casting, and nitridation. The reaction-bonded silicon nitride (RBSN) crucibles after oxidation were found pure enough for silicon ingot growth. More importantly, they could be reused after ingot growth. With the present examples, the potential of using the kerf-loss silicon for fine ceramics is prominent. 相似文献
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Baek Mi-eun Ameer Kashif Jo Yunhee Chung Namhyeok Choi Minji Kim Jung-ok Won Jaehee Lee Sang-Han Kwon Joong-Ho 《Food science and biotechnology》2020,29(5):705-715
Food Science and Biotechnology - Medicinal herbs comprise of heavy microbial contaminations. This study aimed to assess microbial hazards including foodborne pathogens in 20 commercial medicinal... 相似文献
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I.V. Ciuchi C.C. Chung C.M. Fancher C. Capiani J.L. Jones L. Mitoseriu C. Galassi 《Journal of the European Ceramic Society》2018,38(4):1479-1487
Pb0.97La0.03(Zr0.9Ti0.1)0.9925O3 (PLZT 3/90/10) ceramics prepared by solid-state reaction with the compositions near the antiferroelectric/ferroelectric (FE/AFE) phase boundary were studied. From the polarization–electric field P(E) dependence and ex situ X-ray study, an irreversible electric field induced AFE-to-FE phase transition is verified at room temperature. Dielectric and in situ temperature dependent X-ray analysis evidence that the phase transition sequence in PLZT 3/90/10-based ceramics can be readily altered by poling. A first order antiferroelectric-paraelectric (AFE-to-PE) transition occurred at?~190 °C in virgin sample and at?~180 °C in poled sample. In addition, a FE-to-AFE transition occurs in the poled ceramic at much lower temperatures (~120 °C) with respect to the Curie range (~190 °C). The temperature-induced FE-to-AFE transition is diffuse and takes place in a broad temperature range of 72–135 °C. The recovery of AFE is accompanied by an enhancement in the piezoelectric properties. 相似文献
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This study presents a back-analysis of geotechnical parameters on prefabricated vertical drain improved ground at a site in the Mekong Delta. Various time?settlement behaviors that reflected different clay thicknesses and loading patterns were observed. The total surface settlement behavior at several monitoring locations was simulated using an updated exponential method that considered staged construction. The analyzed results were validated by substituting the values into a theoretical solution for radial consolidation. The estimated theoretical behaviors were comparable with the monitored behaviors. The geotechnical parameters were back-analyzed by applying the previously analyzed results to various theoretical and empirical formulas. However, the use of extensometer data that were installed at large intervals produced different values of the geotechnical properties. Furthermore, finite element analysis supported the back-analyzed total settlement behaviors and nearly disregarded the application of the geotechnical properties that were obtained using either surface or subsurface settlement data. However, settlements and excess pore pressures in the sublayers were not successfully predicted even when the geotechnical properties were adjusted. Thus, subsurface instruments that can be installed closely in thick clay deposits are required to reliably reevaluate the variations in geotechnical properties along a certain depth. 相似文献
9.
Agricultural culture is a productive activity about education and management.
It aims at high efficiency and high quality, uses technology as its means, and takes nature
as its carrier. Agricultural cultural resources are the product of the rapid development of
modern economy. It promotes the development of the national economy and profoundly
affects people's production and life. DEA model, also known as data envelope analysis
method, is an algorithm that uses multiple data decision units for input and output
training to obtain the final model. This article explains the concept and basic
characteristics of agricultural culture. Through questionnaire surveys and expert
interviews, we collected development data, screened human, material, and financial data,
and calculated information on economic and social resources. On this basis, this paper
establishes the evaluation index of agricultural culture based on DEA model. Then,
through empirical analysis from a specific perspective, it can be concluded that
increasing human, material and financial input can achieve economic and social benefits. Generally speaking, cultural investment can promote the development of the industry.
The research results of this paper laid a theoretical foundation for the development of
agricultural culture, and put forward a development model focusing on technology
development, improving investment efficiency, and investing in material resources. 相似文献
10.
Yong Joo Park Kwang Ho Lee Mi Seon Jeon Yong Hoon Lee Yoon Joo Ko Changhyun Pang Bonglee Kim Kyu Hyuck Chung Ki Hyun Kim 《International journal of molecular sciences》2020,21(23)
Rhubarb is a well-known herb worldwide and includes approximately 60 species of the Rheum genus. One of the representative plants is Rheum palmatum, which is prescribed as official rhubarb due to its pharmacological potential in the Korean and Chinese pharmacopoeia. In our bioactive screening, we found out that the EtOH extract of R. palmatum inhibited hepatic stellate cell (HSC) activation by transforming growth factor β1 (TGF-β1). Chemical investigation of the EtOH extract led to the isolation of chrysophanol 8-O-glucoside, which was determined by structural analysis using NMR spectroscopic techniques and electrospray ionization mass spectrometry (ESIMS). To elucidate the effects of chrysophanol 8-O-glucoside on HSC activation, activated LX-2 cells were treated for 48 h with chrysophanol 8-O-glucoside, and α-SMA and collagen, HSC activation markers, were measured by comparative quantitative real-time PCR (qPCR) and western blotting analysis. Chrysophanol 8-O-glucoside significantly inhibited the protein and mRNA expression of α-SMA and collagen compared with that in TGF-β1-treated LX-2 cells. Next, the expression of phosphorylated SMAD2 (p-SMAD2) and p-STAT3 was measured and the translocation of p-STAT3 to the nucleus was analyzed by western blotting analysis. The expression of p-SMAD2 and p-STAT3 showed that chrysophanol 8-O-glucoside strongly downregulated STAT3 phosphorylation by inhibiting the nuclear translocation of p-STAT3, which is an important mechanism in HSC activation. Moreover, chrysophanol 8-O-glucoside suppressed the expression of p-p38, not that of p-JNK or p-Erk, which can activate STAT3 phosphorylation and inhibit MMP2 expression, the downstream target of STAT3 signaling. These findings provided experimental evidence concerning the hepatoprotective effects of chrysophanol 8-O-glucoside against liver damage and revealed the molecular basis underlying its anti-fibrotic effects through the blocking of HSC activation. 相似文献