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High-efficiency crystalline carbon nitride photocatalysts:Status and perspectives

Nano research 2024年第9期17卷 7840-7863页

作者： Wenji Pu Yunqiao Zhou Lingfeng Yang Haifeng Gong Yuhan Li Qingyu Yang Dieqing Zhang Engineering research Center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Key Laboratory of Catalysis and New Environmental MaterialsChongqing Technology and Business UniversityChongqing 400067China The Education Ministry Key Lab of Resource chemistry Joint International Research Laboratory of Resource Chemistry of Ministry of EducationShanghai Key Laboratory of Rare Earth Functional Materialsand Shanghai Frontiers Science Center of Biomimetic CatalysisShanghai Normal UniversityShanghai 200234China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Crystallinity and crystal structure greatly influence the photocatalytic behavior of *** g-C3N4 produced by traditional thermal-induced polycondensation reaction bears low crystallinity and thus poor photoactivity,which originates from the incomplete polymerization of the precursor containing amine groups,abundant hydrogen bonds,and unreacted amino,as well as cyanide functional groups in the *** photocatalytic process,these residual functional groups often work as electron trap sites,which may hinder the transfer of electrons on the plane,resulting in low ***,crystalline carbon nitride(CCN)was reported as a promising photocatalyst because its increased crystallinity not only reduces the number of carriers recombination centers,but also increases charge conductivity and improves light utilization due to extendedπ-conjugated systems and delocalizedπ-*** such,we summarize the recent studies on CCN-based photocatalysts for the photoactivity ***,the unique structure and properties of CCN materials are ***,the preparation methods and modification strategies are well *** also sum up the applications of CCN-based materials in the environmental purification and energy ***,this review concerning CNN materials ends with prospects and challenges in the obtainment of high crystallinity by effective techniques,and the deep understanding of photocatalytic mechanism.

关键词： crystalline carbon nitride preparation method modification strategy photocatalytic application

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Pd-catalyzed intermolecular Si–O formation via Si–C activation

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Science China chemistry 2024年第8期67卷 2661-2669页

作者： Shuang Liu Yu-Shu Chen Yichen Wu Peng Wang State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai 200032China School of chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China College of Material chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistryand Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China

The development of efficient Si–O bond formation reaction with 100% atom-economy, excellent functional group tolerance, and broad scope under mild conditions is highly desired due to the prevalence of silanol, silyl ether, and their derivatives in synthetic chemistry and materials science. Here, we have realized the Pd-catalyzed Si–O formation reaction via a Si–C activation approach with 100% atom-economy by employing silacyclobutanes(SCBs) and various hydroxy-containing substrates, including water,alcohols, phenols, and silanols. This protocol features a broad substrate scope, remarkable functional compatibility and mild conditions, providing a series of silanols, silyl ethers in high efficiency. Notably, this protocol could also be used for selective protection of hydroxy functionalities, and for the access of a class of novel polymers containing Si–O main chain. Preliminary mechanistic studies unveiled that this reaction underwent a Pd-catalyzed concerted ring-opening mechanism.

关键词： Si–O formation Si–C activation palladium silacyclobutane silanol silyl ether

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Optimizing the Diameter of Plugging Balls in Deep Shale Gas Wells

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Fluid Dynamics & Materials Processing 2024年第3期20卷 609-624页

作者： Yi Song Zheyu Hu Cheng Shen Lan Ren Xingwu Guo Ran Lin Kun Wang Zhiyong Zhao Shale Gas research Institute PetroChina Southwest Oil&Gasfield CompanyChengdu610056China State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China National Pipe Network group Sichuan East natural Gas Transmission Pipeline Co. Ltd.Wuhan430205China Fracturing Acidizing Company Downhole Operation Company of Chuanqing Drilling Engineering Co.Ltd.Chengdu610213China

Deep shale gas reserves that have been fractured typically have many relatively close perforation holes. Due to theproximity of each fracture during the formation of the fracture network, there is significant stress interference,which results in uneven fracture propagation. It is common practice to use “balls” to temporarily plug fractureopenings in order to lessen liquid intake and achieve uniform propagation in each cluster. In this study, a diameteroptimization model is introduced for these plugging balls based on a multi-cluster fracture propagationmodel and a perforation dynamic abrasion model. This approach relies on proper consideration of the multiphasenature of the considered problem and the interaction force between the involved fluid and solid phases. Accordingly,it can take into account the behavior of the gradually changing hole diameter due to proppant continuousperforation erosion. Moreover, it can provide useful information about the fluid-dynamic behavior of the consideredsystem before and after plugging. It is shown that when the diameter of the temporary plugging ball is1.2 times that of the perforation hole, the perforation holes of each cluster can be effectively blocked.

关键词： Deep shale gas fracture propagation fluid mechanics fluid-solid coupling perforation hole abrasion

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Alloy as advanced catalysts for electrocatalysis:From materials design to applications

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Chinese Chemical Letters 2024年第6期35卷 104-122页

作者： Pingfan Zhang Shihuan Hong Ning Song Zhonghui Han Fei Ge Gang Dai Hongjun Dong Chunmei Li Advanced Chemical Engineering Laboratory of Green Materials and Energy of Jiangsu Province Institute of Green Chemistry and Chemical TechnologySchool of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013China Daqo group Co.Ltd. Zhenjiang 212221China Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin Provincial Key Laboratory of Water Resource and EnvironmentCollege of New Energy and EnvironmentJilin UniversityChangchun 130021China

With the deep integration of electrochemical research with energy,environment,catalysis,and other fields,more and more new electrochemical catalytic reactions have entered our research *** catalysts have recently emerged as a new type of nanomaterial due to the rapid development of kinetic controlled synthesis *** materials offer several advantages over monometallic catalysts,including larger element combinations,complex geometries,bifunctional sites,and reduced use of precious *** paper provides a review of alloy electrocatalysts that are designed and prepared specifically for electrocatalytic *** use of alloy materials in electrocatalyst design is also discussed,highlighting their widespread application in this ***,various synthesis methods and synthesis mechanisms are systematically *** that,by correlating the properties of materials with the structure,relevant strategies toward advanced alloy electrocatalysts including composition regulation,size,morphology,surface engineering,defect engineering,interface engineering and strain engineering are *** addition,the important electrocatalytic applications and mechanisms of alloy electrocatalysts are described and ***,the current challenges and prospects regarding the development of alloy nanomaterials are *** review serves as a springboard from a fundamental understanding of alloy structural dynamics to design and various applications of electrocatalysts,particularly in energy and environmental sustainability.

关键词： Alloy Nanomaterial Electrocatalyst Materials design Electrocatalysis

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Anti-obesity effects of fucoidan from Sargassum thunbergii in adipocytes and high fat diet induced obese mice through inhibiting adipogenic specific transcription factor

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Food Science and Human Wellness 2024年第3期13卷 1608-1616页

作者： Hyo-Geun Lee H.H.A.C.K.Jayawardhana Fengqi Yang D.P.Nagahawaththa N.M.Liyanage Kyung-Mo Song Yun-Sang Choi Seung-Hong Lee You-Jin Jeon Min-Cheol Kang Department of Marine Life Sciences Jeju National UniversityJeju 63243Republic of Korea Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea research group of Food Processing Korea Food Research InstituteWanju 55365Republic of Korea Department of Pharmoceutical Engineering Soonchunhyang UniversityAsan 31538Republic of Korea

The prevalence of obesity has increased and is a health concern *** to the concerns regarding synthetic anti-obesity treatments,nowadays natural products become a *** studies proved that there is a potential to use marine algae as anti-obesity ***,in this study,the lipid inhibitory effect of crude polysaccharide of amyloglucosidase-assisted hydrolysate from Sargassum thunbergii(STAC)and its fucoidan fractions(STAFs)on 3T3-L1 cells and high-fat diet(HFD)-induced obese mice were *** to the results,the STAF3,showed the highest xylose content and exhibited significant inhibitory effects on lipid accumulation by downregulating adipogenic and lipogenic proteins in 3T3-L1 ***,oral supplementation with STAC significantly declined gain in body weight and fat weight,and serum lipid contents in an HFD-induced obesity mouse *** and chemical characterizations demonstrated that puritied STAF3 has consistent surface morphology and small particle size,with similar structural characteristics as commercial ***,these results indicate that STAC and purified STAF3 from Sargassum thunbergia is a potent source to develop as ananti-obesity agents or functional food products to counter obesity.

关键词： Sargassum thunbergii Fucoidan Anti-obesity Anti-steatosis

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胶束催化体系中的对映选择性环醚化反应(英文)

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催化学报 2011年第2期32卷 231-234页

作者： Bhupesh S. SAMANT Sunil S. BHAGWAT natural product and medicinal chemistry research group Division of Pharmaceutical chemistryFaculty of Pharmacy Rhodes University Grahamstown Department of Chemical Engineering Institute of Chemical Technology

The enantioselective cycloetherification of substituted keto phenols into their corresponding dihydrobenzofuran derivatives was carried out using hydrogen peroxide and chiral quaternary ammonium iodide in micellar media. This approach increased the conversion rate of cycloetherification and also widened the scope of this particular reaction for various substituted keto phenols with electron withdrawing as well as electron donating functionalities. The use of a surfactant in the cycloetherification reaction increased the yield of the corresponding enantioselective dihydrobenzofuran four times. The conversion rate of keto phenols into their corresponding dihydrobenzofuran derivatives was proportional to the concentration of the surfactant used in the reaction.

关键词： enantioselective cycloetherification dihydrobenzofuran derivative micellar catalysis

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Inhibitory actions of Pseuderanthemum palatiferum(Nees) Radlk. leaf ethanolic extract and its phytochemicals against carbohydrate-digesting enzymes

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Asian Pacific Journal of Tropical Biomedicine 2016年第2期6卷 93-99页

作者： Pawitra Pulbutr Somsak Nualkaew Sakulrat Rattanakiat Benjamart Cushnie Achida Jaruchotikamol Pharmaceutical chemistry and natural product research Unit Faculty of Pharmacy Mahasarakham University

Objective: To investigate the effects of the leaf ethanolic extract of Pseuderanthemum palatiferum(PPE) and its isolated phytochemicals, stigmasterol and sitosterol-3-O-b-Dglucopyranoside, against a-amylase and a-glucosidase enzyme activities both in vitro and in ***: A concentration of maltose, which is a product released in a-amylase-catalyzing reaction, was used as an index of in vitro a-amylase activity. Meanwhile, in vitro a-glucosidase enzyme activity was indicated by the amount of liberated p-nitrophenol in a-glucosidase-catalyzing reaction. In vivo a-amylase and a-glucosidase enzyme activities were evaluated in the normal rats by using oral starch tolerance test and oral sucrose tolerance test, ***: PPE exerted a concentration-dependent inhibitory action against both aamylase and a-glucosidase in vitro with the IC_(50) values of(11.79 ± 8.10) mg/m L and(1.00 ± 0.11) mg/m L, respectively. Stigmasterol and sitosterol-3-O-b-D-glucopyranoside also exerted an in vitro a-amylase inhibition with the IC_(50) values of(59.41 ± 8.22) mg/m L and(111.19 ± 9.02) mg/m L, respectively. However, these phytochemicals did not produce a concentration-dependent inhibition against in vitro a-glucosidase activity. PPE and its isolated phytochemicals significantly decreased the blood glucose levels at t = 30 min in the oral starch tolerance test. From the sucrose tolerance test, only PPE but not its isolated phytochemicals significantly caused a depletion in the blood glucose levels at t = 30 min Conclusions: These results indicate an inhibitory action against carbohydrate-digesting enzymes as the anti-diabetic mechanism of action of PPE. Nonetheless, further clinical study is required to justify its role in the treatment of diabetes.

关键词： Pseuderanthemum palatiferum Diabetes mellitus a-Amylase a-Glucosidase Postprandial blood glucose

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Optimal Scheduling of Regional Integrated Energy Systems Considering Hybrid Demand Response

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1208-1219页

作者： Ganyun Lyu Bin Cao Dexiang Jia Nan Wang Jun Li Guangyu Chen Department of Electrical Engineering Nanjing Institute of TechnologyNanjing 211167China State Grid Energy research Institute Co. LTDBeijing 102209China State Grid Integrated Energy Service group Co. LTDBeijing 100032China IEEE CSEE

Flexible load can optimize the load curve,which is an important means to promote renewable energy *** peculiarities of electricity,heat,cooling and gas loads are analyzed in this paper,considering the fuzzy degree of human perception for water temperature,and the characteristic model of hot water load is *** the fuzzy degree of human perception of ambient temperature,the characteristic model of cooling load is established by using PMV and PPD ***,considering four combinations of cut load,translatable load,transferable load and alternative load,and considering the coupling relationship of composite parts,different response models of load are established *** the minimum cost of the system,including operation and compensation costs as the objective function,the optimization scheduling model of the regional integrated energy system is established,and the Gurobi solver is used for simulation analysis to solve the optimal output and load response curve of each piece of *** results show that the load curve can be optimized,the flexible regulation ability of the regional integrated energy system can be enhanced,the energy loss of the system can be reduced,and the wind power consumption ability of the system can be increased by considering the integrated demand response.

关键词： Alternative load day ahead optimal scheduling integrated demand response PMV and PPD index regional integrated energy system

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Accelerating BERT inference with GPU-efficient exit prediction

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Frontiers of Computer Science 2024年第3期18卷 31-42页

作者： Lei LI Chengyu WANG Minghui QIU Cen CHEN Ming GAO Aoying ZHOU Shanghai Engineering research Center of Big Data Management School of Data Science and EngineeringEast China Normal UniversityShanghai 200062China Alibaba group Hangzhou 311121China KLATASDS-MOE School of StatisticsEast China Normal UniversityShanghai 200062China

BERT is a representative pre-trained language model that has drawn extensive attention for significant improvements in downstream natural Language Processing(NLP)*** complex architecture and massive parameters bring BERT competitive performance but also result in slow speed at model inference *** speed up BERT inference,FastBERT realizes adaptive inference with an acceptable drop in accuracy based on knowledge distillation and the early-exit ***,many factors may limit the performance of FastBERT,such as the teacher classifier that is not knowledgeable enough,the batch size shrinkage and the redundant computation of student *** overcome these limitations,we propose a new BERT inference method with GPU-Efficient Exit Prediction(GEEP).GEEP leverages the shared exit loss to simplify the training process of FastBERT from two steps into only one step and makes the teacher classifier more knowledgeable by feeding diverse Transformer outputs to the teacher *** addition,the exit layer prediction technique is proposed to utilize a GPU hash table to handle the token-level exit layer distribution and to sort test samples by predicted exit *** this way,GEEP can avoid batch size shrinkage and redundant computation of student *** results on twelve public English and Chinese NLP datasets prove the effectiveness of the proposed *** source codes of GEEP will be released to the public upon paper acceptance.

关键词： BERT FastBERT inference acceleration model distillation early exit text classification

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Decarboxylative Amination with Nitroarenes via Synergistic Catalysis

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Chinese Journal of chemistry 2024年第4期42卷 351-355页

作者： Meiling Ding Sitian Zhou Shunruo Yao Chengjian Zhu Weipeng Li Jin Xie State Key Laboratory of Coordination chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan450001 China

In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary *** protocol is performed at mild conditions without the use of noble metals as catalysts.A wide range of structurally diverse secondary amines could be obtained in good yields(up to 94%)with good functional group *** transformation shows good to excellent selectivity,avoiding the generation of over alkylated byproducts.

关键词： Nitroarenes Amines Synergistic catalysis Carboxylic acids Radical alkylation Amination Photocatalysis Steric hindrance

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