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Lanostane-Type Triterpenoids from Scilla scilloides and Structure Revision of drimiopsin d

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Natural Products and Bioprospecting 2015年第5期5卷 263-270页

作者： Fu-Cai Ren Li-Xia Wang Qin Yu Xian-Jun Jiang Fei Wang BioBioPha Co. Ltd.Kunming 650201People’s Republic of China

Two hitherto unknown lanostane-type triterpenoids,namely scillascillol(1)and scillascillone(2),and a hitherto unknown norlanostane-triterpene glycoside,namely scillascilloside B-1(3),were isolated from the ethanol extract of the whole plants of Scilla *** structures were elucidated on the basis of extensive spectroscopic *** addition,the structure of drimiopsin d(6a)has been revised as 2,5-dimethoxy-8-methyl-1,3,6-trihydroxyxanthone(6)by reanalysis of the spectroscopic data.

关键词： Scilla scilloides Lanostane Scillascillol Scillascillone Structure revision

Co-aromatization of methane and hexane over Pt encapsulated in ZSM-5 zeolite and the electronic effect of K promoters

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Science China Chemistry 2024年第3期67卷 1017-1027页

作者： Bei Liu Fan Wang Xiaomeng dou Pengfei Li Hongwei Xiang Yong Yang Peng He State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China department of Chemistry Tsinghua UniversityBeijing 100084China National energy R&d Center for Coal to Liquid Fuels Synfuels China Technology Co.Ltd.Beijing 101407China University of Chinese Academy of Sciences Beijing 101408China Leibniz-Institut für Katalyse e.V.an der Universitat Rostock Rostock 18059Germany

The co-aromatization of methane with higher hydrocarbons represents a promising route to valorize methane, an abundant but underexploited carbon resource. In this study, we elucidate a novel approach to enhance the catalytic co-aromatization of hexane and methane by confining Pt within zeolite catalysts and modulating its electron density. Our findings show that encapsulating Pt within MFI structure is pivotal for activating the feedstock and fostering the formation of aromatic products. Interaction between K atoms and the silanol nest forms siloxy groups which are critical for the stabilization of Pt species. Tuning the K content in PtSn@MFI catalysts adeptly alters the electronic configuration of Pt clusters. This modification is corroborated by infrared and X-ray photoelectron spectroscopy analysis, and density functional theory calculations. Remarkably, the catalyst with 0.8 wt% K exhibits an optimal Pt electron density, driving its superior efficacy in the co-aromatization reaction, converting 0.78 mol of methane for each mole of hexane processed. By employing ~(13)C isotopic labeling and solid-state NMR studies, we demonstrate the participation of methane in the adsorbed species inside the zeolite channel and its incorporation to the benzyl site of the substitute group and phenyl rings in aromatic compounds, underscoring the importance of Pt encapsulation.

关键词： Pt encapsulation MFI zeolite methane activation co-aromatization ^(13)C solid-state NMR

Forecasting solar still performance from conventional weather data variation by machine learning method

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Chinese Physics B 2023年第4期32卷 19-25页

作者：高文杰沈乐山孙森山彭桂龙申震王云鹏 AbdAllah Wagih Kandeal 骆周扬 A.e.Kabeel 张坚群鲍华杨诺 State Key Laboratory of Coal Combustion and School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China Zhejiang Baima Lake Laboratory Co. Ltd.Hangzhou 31121China Zhejiang energy Group R&d Institute Co.Ltd.Hangzhou 311121China Zhejiang Zheneng Yueqing electric Power Generation Co. Ltd.Yueqing 325609China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China Mechanical engineering department Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh 33516Egypt Mechanical Power engineering department Faculty of EngineeringTanta UniversityTantaEgypt Faculty of engineering Delta University for Science and TechnologyGamasaEgypt

Solar stills are considered an effective method to solve the scarcity of drinkable ***,it is still missing a way to forecast its ***,it is proposed that a convenient forecasting model which just needs to input the conventional weather forecasting *** model is established by using machine learning methods of random forest and optimized by Bayesian *** required data to train the model are obtained from daily measurements lasting9 *** validate the accuracy model,the determination coefficients of two types of solar stills are calculated as 0.935and 0.929,respectively,which are much higher than the value of both multiple linear regression(0.767)and the traditional models(0.829 and 0.847).Moreover,by applying the model,we predicted the freshwater production of four cities in *** predicted production is approved to be reliable by a high value of correlation(0.868)between the predicted production and the solar *** the help of the forecasting model,it would greatly promote the global application of solar stills.

关键词： solar still production forecasting forecasting model weather data random forest

关于具有测边导坑和有限岩石覆盖层的隧道开口的离散分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2018年第4期19卷 255-265页

作者： Chia Weng BOON Chee Wei NeO david Chew Chiat NG Victor Chee Wee ONG One Smart engineering Pte ltd. 658065 Singapore

目的:针对新加坡的花岗岩地质结构,研究将典型马蹄形隧道挖掘成双拱隧道时岩石支撑的设计问题。利用离散元法分析侧边导坑对隧道主体开口的影响。创新点:1.基于平面应变假设,提出一个针对性的离散元模型以分析侧边导坑的设置对主体隧道... 详细信息

目的:针对新加坡的花岗岩地质结构,研究将典型马蹄形隧道挖掘成双拱隧道时岩石支撑的设计问题。利用离散元法分析侧边导坑对隧道主体开口的影响。创新点:1.基于平面应变假设,提出一个针对性的离散元模型以分析侧边导坑的设置对主体隧道支撑的影响;2.此模型适用于解决底下长跨度开口的支撑设计问题,如大众捷运系统隧道和紧贴式双孔隧道的建造,补充了传统经验主义的设计方法。方法:1.采用离散元法对马蹄形隧道开口支撑问题进行非连续分析;2.采用二维平面应变模型简化问题。结论:1.离散元法可用于分析有限岩石覆盖层的失效机制,单隧道支撑要求以及增加侧边导坑后的支撑要求;2.模型计算结果显示,侧边导坑的挖掘使得支柱总的螺栓连接作用力增加了一倍。

关键词：岩石覆盖层双隧道侧边导坑支柱离散元法

Inoculation of Chlorella and Food Waste Improves the Physio-Morphological Features of Red Pepper by Regulating Activating Antioxidant defense System

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Phyton-International Journal of experimental Botany 2023年第9期92卷 2699-2711页

作者： Sang-Mo Kang Shifa Shaffique Muhammad Imran Su-Mi Jeon Shabir Hussain Wani Muhammad Aaqil Khan Peter Odongkara eun-Hae Kwon Yosep Kang Joon-Ik Son Won-Chan Kim In-Jung Lee department of Applied Biosciences Kyungpook National UniversityDaegu41566Korea Biosafety division National Institute of Agriculture ScienceRural Development AdministrationJeonju54874Korea department of Technical Support Daegu City Agricultural Technology CenterDaegu41159Korea department of Chemical and Life Sciences Qurtuba University of Science and Information TechnologyPeshawarPakistan Mountain Research for Field Crops Khudwani Shere-e-Kashmir University of Agriculture Sciences and Technology SrinagarJamu and KashmirIndia corporate Affiliated Research Institute Seyen Co.Ltd.Kyungsan38561Korea

Food waste is recognized as a valuable source for potential agricultural applications to supply organic matter and nutrients to arable ***,the information on the combined application of food waste and the plant growth-promoting bacterial strain,Chlorella,related to plant metabolic features and sodium chloride content in arable soil is *** present study was conducted to investigate the exogenous application of food waste along with Chlorella,which improved the physio-morphological features of red *** results revealed that this combination enhanced the organic matter in the soil,ultimately improving the fertility rate of the soil,and the physio-morphological features,such as chlorophyll a content(24.5±0.7),root(7.8±0.7)cm and shoot length(12.1±0.7)cm,fresh weight(2.1±0.05)g,dry weight(0.19±0.05)g,mineral contents,and hormonal concentration(ABA by up to 2 folds).The combined treatment also minimized free radicals via the activation of the intrinsic antioxidant series cascade and electrolyte *** findings showed that adding Chlorella and food wastes improved growth characteristics and can be used as a green bio-fertilizer for sustainable agriculture.

关键词： Food waste Chlorella hormone antioxidant

Comprehensive evaluation Model of Reservoir Operation Based on Improved Set Pair Analysis

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Transactions of Tianjin University 2013年第1期19卷 25-28页

作者：任炳昱孙宜超周正印程正飞胡兴富 State Key Laboratory of Hydraulic engineering Simulation and Safety Tianjin University Chongqing Yutan Reservoir Company Ltd.

A comprehensive evaluation model based on improved set pair analysis is established. Considering the complexity in decision-making process, the model combines the certainties and uncertainties in the schemes, i.e., identical degree, different degree and opposite degree. The relations among different schemes are studied, and the traditional way of solving uncertainty problem is improved. By using the gray correlation to determine the difference degree, the problem of less evaluation indexes and inapparent linear relationship is solved. The difference between the evaluation parameters is smaller in both the fuzzy comprehensive evaluation model and fuzzy matter-element method, and the dipartite degree of the evaluation result is unobvious. However, the difference between each integrated connection degree is distinct in the improved set pair analysis. Results show that the proposed method is feasible and it obtains better effects than the fuzzy comprehensive evaluation method and fuzzy matter-element method.

关键词： set pair analysis comprehensive evaluation model gray correlation reservoir operation

STUdY ON BIOLeACHING OF PRIMARY CHALCOPYRITe ORe WITH THeRMOACIdOPHLIC ARCHAe

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Acta Metallurgica Sinica(english Letters) 2006年第5期19卷 341-346页

作者： P. Zou W.B. Zhang T. Lei J.K. Wang Kunming University of Science and Technology Kunming 650093 China Technology Center Yunnan Metallurgy Group Co. Ltd. Kunming 650031China

A high temperature-tolerating thermoacidophilic archae （TA） was isolated from water samples collected from a hot sulfur-containing spring in the Yunnan Province, China, and was used in bioleaching experiments of a low-grade chalcopyrite ore. The TA grow at temperatures ranging from 40 to 80℃, with 65℃ being the optimum temperature, and at pH values of l.5 to 4.0, with an optimum pH value of 2.0. The bioleaching experiments of the chalcvpyrite ore were conducted in both laboratory batch bioreactors and leaching columns. The results obtained from the bioreactor experiments showed that the TA bioleaching rate of copper reached 97% for a 12-day leaching period, while the bioleaching rate was 32.43% for thiobacillus ferrooxidans （Tf） leaching for the same leaching time. In the case of column leaching, tests of a two-phase leaching （196 days）, that is, a two-month （56 days） Tf leaching in the first phase, followed by a 140-day TA leaching in the second phase were performed. The average leaching rate of copper achieved for the 140-day TA leaching was 195mg/（L.d）, while for the control experiments, it was as low as 78mg/（L .d） for the Tf leaching, indicating that the TA possesses a more powerful oxidizing ability to the chalcopyrite than Tf Therefore, it is suggested that the two-phase leaching process be applied to .for the heap leaching operations, whereas, the TA can be used in the second phase when the temperature inside the heap has increased, and the primary copper sulfide minerals have already been partially oxidized with Tf beforehand in the first phase.

关键词： chalcopyrite biological oxidation thermoacidophilic archae mesophile batch stirred bioleaching column bioleaching

enhancing cycle stability of Li metal anode by using polymer separators coated with Ti-containing solid electrolytes

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Rare Metals 2021年第6期40卷 1357-1365页

作者： Zhao Yan Hong-Yi Pan Jun-Yang Wang Ru-Song Chen Quan Li Fei Luo Xi-Qian Yu Hong Li Beijing Advanced Innovation Center for Materials Genome engineering Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Tianmulake excellent Anode Materials Co. Ltd.Liyang 213300China Yangtze River delta Physics Research Center Co. Ltd.Liyang 213300China

The employment of lithium metal anode in rechargeable lithium batteries has been hindered by the safety concerns which are associated with the uncontrolled lithium dendrite growth and the unceasing side reactions with liquid *** this work,we report that the use of Ti-containing solid electrolyte-coated separators can greatly enhance the cycle performances of lithium metal anode in cells using liquid *** detailed morphologic studies indicate that more uniform lithium deposition is achieved in cells using Ti-containing solid electrolyte-coated separators than that using Al_(2)O_(3)-coated separators,which is likely due to the modified anode and electrolyte interfacial properties induced by the reactive nature of Ti-containing solid electrolytes with metallic *** work demonstrates an effective strategy to enhance the homogeneity of lithium deposition,which leads to the stable cycling of lithium metal anode in rechargeable lithium-ion batteries.

关键词： Lithium metal anode Lithium batteries Solid electrolyte Separator

defect-mode and Fabry-Perot resonance induced multi-band nonreciprocal thermal radiation

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Science China(Technological Sciences) 2024年第8期67卷 2405-2412页

作者： CHeN ZiHe YU ShiLv YUAN Cheng CUI XinYou HU Run School of energy and Power engineering Huazhong University of Science and TechnologyWuhan 430074China Wuhan Fiberhome Fuhua electric Co. Ltd.Wuhan 430074China

According to Kirchhoff's radiation law,the spectral-directional absorptivity(α)and spectral-directional emissivity(e)of an object are widely believed to be identical,which places a fundamental limit on photonic energy conversion and *** introduction of Weyl semimetals and magneto-optical(MO)materials into photonic crystals makes it possible to violate Kirchhoff's law,but most existing work only report the unequal absorptivity and emissivity spectra in a single band,which cannot meet the requirements of most practical ***,we introduce a defect layer into the structure composed of one-dimensional(1d)magnetophotonic crystal and a metal layer,which realizes dual-band nonreciprocal thermal radiation under a 3-T magnetic field with an incident angle of 60°.The realization of dual-band nonreciprocal radiation is mainly due to the Fabry-Perot(FP)resonance occurring in the defect layer and the excitation of Tamm plasmon,which is proved by calculating the magnetic field *** addition,the effects of incident angle and structural parameters on nonreciprocity are also *** is more,the number of nonreciprocal bands could be further increased by tuning the defect layer *** the defect layer thickness increases to 18.2μm,tri-band nonreciprocal thermal radiation is realized due to the enhanced number of defect modes in the photonic band gap and the FP resonance occurring in the defect ***,the effect of defect location on nonreciprocity is also *** present work provides a new way for the design of multi-band or even broad-band nonreciprocal thermal emitters.

关键词： Kirchhoff's law multi-band nonreciprocal thermal radiation magnetophotonic crystal Tamm plasmon defect layer Fabry-Perot resonance