检索结果-南通市图书馆

Donor-acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic H_(2)generation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 5835-5844页

作者： Yu liu Yawen Shi hua Wang Shengbo Zhang Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China School of Environmental Science and Engineering Tianjin Key Laboratory of Biomass/Wastes UtilizationTianjin UniversityTianjin 300350China

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality ***,the lower photocatalytic efficiency due to the limited light trapping capacity,low electron transfer rate,and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical ***,we constructed a series of donor–acceptor(D–A)type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane(AB)*** visible light irradiation at 20℃,PtCo_(2)@covalent organic framework(COF)showed the highest photocatalytic activity with a turnover frequency(TOF)of 486 min−*** and density functional theory(DFT)calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo_(2)***,the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework,and accelerate the photogenerated electron transfer from D–A type COF to PtCo_(2)nanocluster,which promotes the adsorption and activation of H_(2)O and AB molecules and accelerates hydrogen ***,PtCo_(2)@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type *** believe that this work will provide a theoretical guide for the rational design of efficient D–A COFbased catalysts for photocatalysis.

关键词： light trapping electron transfer donor-acceptor covalent organic frameworks(D-A COFs) bimetallic nanoclusters photocatalysis

First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第4期23卷 970-980页

作者： liu Hongwei XING Lei ZHU Henghua ZHANG Jin ZHANG jing liu huaishan Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266071China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Shandong Institute of Geological Survey Jinan 250014China

The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction *** methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling *** this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is ***,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their ***,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking *** from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data.

关键词： first-arrival picking spatial waveform variation label cross-correlation superposition method

Counterion-Mediated Hydrogen Bonding Making Strong Polyelectrolytes pH-Responsive:Current Understanding and Perspectives

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第9期42卷 1270-1277,I0005页

作者： Yue huang Guang-Tao Mei Zan hua Guang-Ming liu Hefei National Research Center for Physical Sciences at the Microscale Department of Chemical PhysicsKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei230026China The Key Laboratory of Functional Molecular Solids Ministry of Educationand Department of Materials ChemistrySchool of Chemistry and Materials ScienceAnhui Normal UniversityWuhu214002China

The counterion-mediated hydrogen bonding(CMHB)is related to the hydrogen bonding between bound counterions and polyelectrolyte chains in polyelectrolyte systems,where the counterions can both electrostatically bind to the charged groups of polyelectrolyte chains and act as hydrogen bond donors or acceptors to form hydrogen bonds with the hydrogen bond sites associated with polyelectrolyte chains simultaneously.A large number of literatures illustrate that strong polyelectrolytes(SPs)are insensitive to pH,which severely limmits the applications of SPs as smart ***,our studies have demonstrated that the CMHB makes SPs *** perspective discusses the mechanism of pH responsiveness of SPs and the pH-tunable properties of SPs,based on the pH-controlled CMHB *** future research directions on the pH responsiveness of SPs are also discussed *** is anticipated that the study of the pH responsiveness of SPs not only will provide a new understanding of the fundamental properties of SPs,but also will greatly expand the applications of SPs in the field of smart materials.

关键词： Counterion binding Hydrogen bond Polyelectrolyte brush Polyelectrolyte complexation

(Parallel) kinetic resolution of 3,3-disubstituted indolines via organocatalyzed reactions with azodicarboxylates

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第3期67卷 973-980页

作者： Qianwen Jiang Dekun Zhang Mengyao Tang hua liu Xiaoyu Yang School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

A novel kinetic resolution(KR) method has been developed for 3,3-disubstituted indolines, whose catalytic asymmetric synthesis remains a significant challenge in organic synthesis. The key to the success of this KR protocol lies in the utilization of chiral phosphoric acid-catalyzed triazane formation reaction with azodicarboxylates, which enables the enantioselective synthesis of various substituted indolines bearing C3-quaternary stereocenters with good to high enantioselectivities(with sfactors up to 70). Moreover, an intriguing parallel kinetic resolution(PKR) has been developed by combining triazane formation and dehydrogenation reactions using different azodicarboxylates. Experimental studies have provided insight into the mechanism of this PKR reaction, demonstrating stereoselectivity in both triazane formation and dehydrogenation steps, favoring the opposite enantiomers. The large-scale synthesis and diverse derivatizations of the products, particularly the imine groupcontaining 3H-indoles, demonstrate the value of these(P)KR methods.

关键词： asymmetric organocatalysis kinetic resolution 3 3-disubstituted indolines azodicarboxylate triazanes

Effectivity and safety of trifocal intraocular lenses and capsular tension rings implantation for cataract patients with axial high myopia

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第3期17卷 499-508页

作者： Shan hua Qiu-Xia Xie Hu Wang jing-Xiang Zhong Dongguan Aier Eye Hospital Jinan UniversityDongguan 523106Guangdong ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Jinan UniversityGuangzhou 510630Guangdong ProvinceChina Department of Ophthalmology the Sixth Affiliated Hospital of Jinan UniversityDongguan 523576Guangdong ProvinceChina

●AIM:To assess effectivity and safety of trifocal intraocular lenses(IOLs)and capsular tension rings in treating cataract patients with axial high myopia.●METHODS:A prospective nonrandomized controlled clinical trial was *** 98 eyes(74 patients)who underwent femtosecond laser-assisted cataract surgery(FLACS)with trifocal IOLs were enrolled in the study and followed up for 2y after surgery:46 eyes(33 patients)with capsular tension ring implantation in the long axial lengths(AL)group(260.05).The dysfunctional lens index and total modulation transfer function(MTF)average height were similar between the two *** postoperative internal coma aberrations in the axial high myopia eyes were significantly higher than that in the normal AL group(P<0.05).The total satisfaction score in the long AL group(91.32±2.76)was slightly higher than that in the normal AL group(90.36±3.47),but there was no difference(P=0.136).A statistically negative correlation was found between corrected distance visual acuity(CDVA)and dysfunctional lens index(r=-0.382,P=0.009),and between CDVA and the total MTF average height(r=-0.374,P=0.01).But there was no significant correlation between CDVA and total satisfaction score(r=0.059,P=0.696).Postoperative complications mainly presented as posterior capsular opacity(PCO),retinal detachment and cystoid macular *** was no difference in the incidenc

关键词： trifocal intraocular lenses capsular tension ring axial high myopia cataract visual quality

Intestinal microecological transplantation for a patient with chronic radiation enteritis:A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第19期30卷 2603-2611页

作者： Lin Wang Yan Li Yu-jing Zhang Li-hua Peng Department of Gastroenterology and Hepatology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Gastroenterology and Hepatology Chinese PLA Medical SchoolBeijing 100853China

BACKGROUND The gut microbiota is strongly associated with radiation-induced gut *** study aimed to assess the effectiveness and safety of intestinal microecological transplantation for treating patients with chronic radiation *** SUMMARY A 64-year-old female with cervical cancer developed abdominal pain,diarrhea,and blood in the stool 1 year after *** electronic colonoscopy was performed to diagnose chronic radiation *** courses of intestinal microecological transplantation and full-length 16S rRNA microbiological analysis were *** patient experienced short-and long-term relief from symptoms without adverse *** 16S rRNA sequencing revealed significant differences in the intestinal flora’s composition between patient and healthy *** bacteria,such as Escherichia fergusonii and Romboutsia timonensis,were more in the *** bacteria such as Faecalibacterium prausnitzii,Fusicatenibacter saccharivorans,Ruminococcus bromii,and Bifidobacterium longum were more in the healthy *** microbiota transplantation resulted in a significant change in the patient's intestinal flora *** composition converged with the donor's flora,with an increase in core beneficial intestinal bacteria,such as Eubacterium rectale,and a decrease in pathogenic *** in the intestinal flora corresponded with the patients'alleviating clinical *** Intestinal microecological transplantation is an effective treatment for relieving the clinical symptoms of chronic radiation enteritis by altering the composition of the intestinal *** study provides a new approach for treating patients with chronic radiation enteritis.

关键词： Chronic radiation enteritis Gut microbial transplantation Intestinal microecology Cancer Quality of life Case report

Accurate Source-Receiver Positioning Method for a High-Resolution Deep-Towed Multichannel Seismic Exploration System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第2期23卷 415-426页

作者： LI jing liu Kai WEI Zhengrong ZHANG Liancheng liu Yangting PEI Yanliang liu Chenguang liu Baohua Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMNRQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266061China College of Ocean Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou 310018China

The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high vertical and horizontal ***,the quality of deep-towed seismic imaging hinges on accurate source-receiver positioning *** light of existing technical problems,we propose a novel array geometry inversion method tailored for high-resolution deep-towed multichannel seismic exploration *** method is independent of the attitude and depth sensors along a deep-towed seismic streamer,accounting for variations in seawater velocity and seabed slope *** approach decomposes the towed line array into multiline segments and characterizes its geometric shape using the line segment distance and pitch *** optimization parameters for seawater velocity and seabed slope angle,we establish an objective function based on the model,yielding results that align with objective *** the particle swarm optimization algorithm enables synchronous acquisition of optimized inversion results for array geometry and seawater *** validation using theoretical models and practical data verifies that our approach effectively enhances source and receiver positioning inversion *** algorithm exhibits robust stability and reliability,addressing uncertainties in seismic traveltime picking and complex seabed topography conditions.

关键词： high-resolution deep-towed multichannel seismic exploration source-receiver positioning array geometry inversion seawater heterogeneity seabed slope angle

Garnet and Zircon U-Pb Geochronology and Geochemistry Reveal Genesis of the Dafang Au-Pb-Zn-Ag Deposit,Southern Hunan

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2024年第3期98卷 717-735页

作者： JIANG hua KONG hua liu Biao TAN Fucheng QIN Yixue huaNG jingang ZHU Yu Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Hunan Baoshan Nonferrous Metals and Minerals Co. Ltd.ChenzhouHunan 424402China

Garnet is a primary mineral in skarn deposits and plays a significant role in recording copious mineralization and metallogenic *** study systematically investigates the geochemistry and geochronology of garnet and zircon in the Dafang Au-Pb-Zn-Ag deposit,which represents prominent gold mineralization in southern Hunan,*** samples with distinct zoning patterns and compositional variations were identified using various analytical techniques,including Backscattered Electron(BSE)imaging,Cathodoluminescence(CL)response,textural characterization,and analysis of rare-earth elements(REE),major contents,and trace element *** garnet was dated U-Pb dating,which yielded a lower intercept age of 161.06±1.93 *** age is older than the underlying granodiorite porphyry,which has a concordia age of 155.13±0.95 Ma determined by zircon U-Pb *** results suggest that the gold mineralization may be related to the concealed *** groups of garnet changed from depleted Al garnet to enriched Al garnet,and the rare earth element(REE)patterns of these groups were converted from light REE(LREE)-enriched and heavy REE(HREE)-depleted with positive europium(Eu)anomalies to medium REE(MREE)-enriched from core to rim *** different REE patterns of garnet in various zones may be attributed to changes in the fluid environment and late superposition *** development of distal skarn in the southern Hunan could be a significant indicator for identifying gold mineralization.

关键词： garnet and zircon U-Pb dating LA-ICP-MS mapping Dafang Southern Hunan

Strong hetero-interface interaction in 2D/2D WSe2/ZnIn2S4 heterostructures for highly-efficient photocatalytic hydrogen generation

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第10期97卷 379-387页

作者： Xu Guo Xing liu jing Shan Zhuo Xu Zhiming Fang Lu Wang Shengzhong liu School of Energy Power and Mechanical Engineering North China Electric Power University Shaanxi Key Laboratory for Advanced Energy Devices School of Materials Science and Engineering Shaanxi Normal University Qinghai Advanced Energy Storage Laboratory SPIC Qinghai Photovoltaic Industry Innovation Center Co. Ltd.State Power Investment Corporation Key Laboratory of Photoelectric Conversion and Utilization of Solar Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen ***,2D/2D WSe2/ZnIn2S4heterostructures with strong hetero-interface interaction and abundant contact were constructed via an impregnation-annealing *** charge transfer from ZnIn2S4to WSe2was evidenced by transient absorption spectroscopy in crafted heterostructures owing to the tight and2D face-to-face *** a result,the prepared WSe2/ZnIn2S4heterostructures exhibited boosted photocatalytic performance and a highest hydrogen evolution rate of 3.377 mmol/（g h） was achieved with an apparent quantum yield of 45.7% at 420 *** work not only provides new strategies to achieve efficient 2D/2D heterostructures but also paves the way for the development of green hydrogen in the future.

关键词： Indium compounds