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Journal of Materials Science & Technology 2023年第23期154卷 129-139页

作者： Mingyi yu Jianbo Wang Guojun li Shule Zhang Qin Zhong School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Indium vanadate (InVO4 ) possesses excellent potential in photocatalytic carbon dioxide (CO_(2) ) reduction, but further modifications of reducing charge recombination and increasing active sites are still needed. Herein, InVO4 /g-C3 N4 (InVO-CN) heterojunction composite photocatalysts were prepared via in situ formation of InVO4 nanoparticles on the lamellar structure of graphite carbon nitride (g-C3 N4 ) containing nitrogen (N) defects. Among these composites, 30% InVO-CN showed the best photoreduction performance for CO_(2) at normal temperature and pressure without sacrificial agent (carbon monoxide, CO: 20.14 μmol g–1 h–1;methane, CH4 : 3.46 μmol g–1 h–1 ), which were 1.8 and 2.8 times higher than these of pure g-C3 N4 and InVO4 . The excellent performance could be attributed to the enhancement of CO_(2) adsorption, and most importantly, the enhanced charge carrier separation and reduction capacity induced by the formation of Z-scheme heterojunction between InVO4 and g-C3 N4 . In this work, intimate heterojunction interfaces between materials were formed by introducing g-C3 N4 with defects in InVO4 , which provides a promising modification scheme.

关键词： Z-scheme heterojunction CO_(2)photoreduction g-C3N4,InVO4

Wind-tunnel experimental studies of the spatial snow distribution over grass and bush surfaces

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Journal of Hydrodynamics 2022年第1期34卷 85-93页

作者： Guang li Jun-ming Qin Hong-xiang yu Ning Huang Key Laboratory of Mechanics on Disaster and Environment in Western China The Ministry of Education of ChinaLanzhou UniversityLanzhou730000China School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China College of Atmospheric Science Lanzhou UniversityLanzhou730000China School of Architecture Civil and Environmental EngineeringSwiss Federal Institute of Technology LausanneLausanneSwitzerland

The snow is one of the most important water resources in grassland in northern and western China, while the wind blowing snow due to the strong wind there is a common phenomenon, which can lead to heavy disasters to harm the local animal husbandry and transportation. A reasonable arrangement of the snow protection forests is one of the most economical and effective methods to prevent the wind blowing snow, and a great number of investigations were carried out for its wind block effects. However, the deposition patterns of the snowfall and the blowing snow in the forests are still largely unknown. In this study, the wind tunnel experiments are performed to investigate the influences of the vegetation (grass and bush) on the wind speed profiles and the spatial distribution of the accumulated snow, by using the bran as the snow substitute. The snow blocking abilities of two bush models are analyzed to show the effects of different coverages. The results show that the grass and the bush have different effects on the wind speed profiles, and the snow-blocking abilities of the vegetation and the resulting spatial distribution are determined by the amount of the snowfall, the wind speed, and the height and the coverage of the vegetation. For the engineering design, if the snow is required on the windward side of the vegetation or in the vegetation, the densely arranged forest belts are needed, if the snow is required to accumulate on the leeward side of the vegetation, the sparse forest belts can be used. This work would be helpful as a reference to the reasonable arrangement of the snow-protection forests in pastoral areas.

关键词： Wind tunnel experiment wind speed profile vegetation snow-protection forest snow blocking ability

A station-data-based model residual machine learning method for fine-grained meteorological grid prediction

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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 155-166页

作者： Chuansai ZHOU Haochen li Chen yu Jiangjiang XIA Pingwen ZHANG School of Mathematical Sciences Peking UniversityBeijing100871China School of Science Beijing University of Posts and TelecommunicationsBeijing100876China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing100029China

Fine-grained weather forecasting data,i.e.,the grid data with high-resolution,have attracted increasing attention in recent years,especially for some specific applications such as the Winter Olympic *** European Centre for Medium-Range Weather Forecasts(ECMWF)provides grid prediction up to 240 hours,the coarse data are unable to meet high requirements of these major *** this paper,we propose a method,called model residual machine learning(MRML),to generate grid prediction with high-resolution based on high-precision stations *** applies model output machine learning(MOML)for stations ***,MRML utilizes these forecasts to improve the quality of the grid data by fitting a machine learning(ML)model to the *** demonstrate that MRML achieves high capability at diverse meteorological elements,specifically,temperature,relative humidity,and wind *** addition,MRML could be easily extended to other post-processing methods by invoking different *** our experiments,MRML outperforms the traditional downscaling methods such as piecewise linear interpolation(Pli)on the testing data.

关键词： machine learning(ML) post-processing fine-grained weather forecasting model residual machine learning(MRML)

Spatial non-stationary characteristics between temperate grasslands based on a mixed geographically weighted regression model

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Journal of Geographical Sciences 2022年第6期32卷 1076-1102页

作者： song Xiaolong MI Nan MI Wenbao li Longtang College of Agriculture Ningxia UniversityYinchuan 750021China School of Geography and Planning Ningxia UniversityYinchuan 750021China

Spatial models are effective in obtaining local details on grassland biomass,and their accuracy has important practical significance for the stable management of grasses and *** this end,the present study utilized measured quadrat data of grass yield across different regions in the main growing season of temperate grasslands in Ningxia of China(August 2020),combined with hydrometeorology,elevation,net primary productivity(NPP),and other auxiliary data over the same ***,non-stationary characteristics of the spatial scale,and the effects of influencing factors on grass yield were analyzed using a mixed geographically weighted regression(MGWR)*** results showed that the model was suitable for correlation *** spatial scale of ratio resident-area index(PRI)was the largest,followed by the digital elevation model,NPP,distance from gully,distance from river,average July rainfall,and daily temperature range;whereas the spatial scales of night light,distance from roads,and relative humidity(RH)were the most *** influencing factors maintained positive and negative effects on grass yield,save for the strictly negative effect of *** regression results revealed a multiscale differential spatial response regularity of different influencing factors on grass *** parameters revealed that the results of Ordinary least squares(OLS)(Adjusted R^(2)=0.642)and geographically weighted regression(GWR)(Adjusted R^(2)=0.797)models were worse than those of MGWR(Adjusted R^(2)=0.889)*** on the results of the RMSE and radius index,the simulation effect also was MGWR>GWR>OLS ***,the MGWR model held the strongest prediction performance(R^(2)=0.8306).Spatially,the grass yield was high in the south and west,and low in the north and east of the study *** results of this study provide a new technical support for rapid and accurate estimation of grassland yield to dynamically adjust grazing decision in the semi-ar

关键词： grass yield spatial non-stationary mixed geographically weighted regression model temperate grassland Ningxia

Influence of binder systems on sintering characteristics, microstructures, and mechanical properties of PcBN composites fabricated by SPS

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Journal of Advanced Ceramics 2022年第2期11卷 321-330页

作者： Shuna CHEN Hengzhong FAN yunfeng SU Wensheng li Jicheng li Bing YAN Junjie song litian HU Yongsheng ZHANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

Cubic boron nitride(cBN)with high hardness,thermal conductivity,wear resistance,and chemical inertness has become the most promising abrasive and machining *** to the difficulty of fabricating pure cBN body,generally,some binders are incorporated among cBN particles to prepare polycrystalline cubic boron nitride(PcBN).Hence,the binders play a critical factor to the performances of PcBN *** this study,the PcBN composites with three binder systems containing ceramic and metal phases were fabricated by spark plasma sintering(SPS)from 1400 to 1700℃.The sintering behaviors and mechanical properties of the composites were *** show that the effect of binder formulas on mechanical properties mainly related to the compactness,mechanical performances,and thermal expansion coefficient of binder phases,which affect the carrying capacity of the composites and the bonding strength between binder phases and cBN *** PcBN composite with SiAlON phase as binder presented optimal flexural strength(465±29 MPa)and fracture toughness(5.62±0.37 MPa·m^(1/2)),attributing to the synergistic effect similar to transgranular and intergranular ***,the excellent mechanical properties can be maintained a comparable level when the temperature even rises to 800℃.Due to the weak bonding strength and high porosity,the PcBN composites with Al_(2)O_(3)–ZrO_(2)(3Y)and Al–Ti binder systems exhibited inferior mechanical *** possible mechanisms to explain these results were also analyzed.

关键词： polycrystalline cubic boron nitride(PcBN) binder system sintering characteristic high temperature mechanical property fracture mechanism

Progress of Animal Research on Electro-acupuncture Treatment for Depression

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Chinese Medical Sciences Journal 2014年第1期29卷 43-47页

作者： yu-ping Mo Hai-jiang Yao Hong-tao song An-ping Xu Yin-shan Tang Zhi-gang li School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese Medicine

This paper summarized the Chinese literatures in the previous 5 years about the pre-clinical animal researches on the application of electro-acupuncture(EA) treatment for depression,searched in China National Knowledge Infrastructure(CNKI).The efficiency of EA treatment for depression and the mechanism of it were discussed,to shed light on new ideas and new fronts for the further research on depression in clinical or pre-clinical fields.

关键词： electro-acupuncture depression animal research review

Methyl functionalization of trimesic acid in copper-based metal-organic framework for ammonia colorimetric sensing at high relative humidity

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Chinese Chemical Letters 2024年第6期35卷 211-215页

作者： yuxin Wang Zhengxuan song yutao liu Yang Chen Jinping li libo li Jia Yao College of Chemical Engineering and Technology Shanxi Key Laboratory of Gas Energy Efficient and Clean UtilizationTaiyuan University of TechnologyTaiyuan 030024China Department of Gastroenterology Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuan 030024China

Exhaled ammonia(NH_(3))can be used as a crucial biomarker of kidney and liver ***,the high humidity in the detection conditions remains a challenge for accurate detection by gas ***,a copper-based metal-organic framework(CH_(3)-Cu-BTC)with methyl(CH_(3)^(-))functionalization of trimesic acid was synthesized for NH_(3) colorimetric *** CH_(3)-Cu-BTC exhibited a strong response for 5 ppm NH_(3) with high selectivity under high relative humidity(75%RH).Density functional theory(DFT)simulations indicated that the NH_(3) molecules interacted more strongly with CH_(3)-Cu-BTC than H_(2)O molecules did,and the corresponding color switching was attributed to the lone-pair electron in NH_(3) changing the coordination environment of Cu^(2+)ions,leading to an obviously visible color switching response from ruby green to *** on the tailor-made pore chemistry,the precise detection of trace amounts of NH_(3) in exhaled air was realized through functionalized MOF *** strategy used in this study not only offers a new pathway for the rapid detection of low concentration NH_(3) under humid conditions,but also shows a method for early respiration diagnosis of kidney and liver diseases.

关键词： Metal-organic framework Ammonia sensing Naked-eye color switching High humidity Respiration diagnosis

Assessment of the cropland classifications in four global land cover datasets： A case study of Shaanxi Province, China

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Journal of Integrative Agriculture 2017年第2期16卷 298-311页

作者： CHEN Xiao-yu liN Ya ZHANG Min yu Le li Hao-chuan BAI yu-qi Key Laboratory for Earth System Modelling Ministry of Education/Department of Earth System Science (DESS) Tsinghua University Beijing 100084 P.R. China National Information Center Beijing 100045 P.R. China

Accurate and reliable cropland surface information is of vital importance for agricultural planning and food security monitoring. As several global land cover datasets have been independently released, an inter-comparison of these data products on the classification of cropland is highly needed. This paper presents an assessment of cropland classifications in four global land cover datasets, i.e., moderate resolution imaging spectrometer （MODIS） land cover product, global land cover map of 2009 （GlobCover2009）, finer resolution observation and monitoring of global cropland （FROM-GC） and 30-m global land cover dataset （GlobeLand30）. The temporal coverage of these four datasets are circa 2010. One of the typical agricultur- al regions of China, Shaanxi Province, was selected as the study area. The assessment proceeded from three aspects： accuracy, spatial agreement and absolute area. In accuracy assessment, 506 validation samples, which consist of 168 cropland samples and 338 non-cropland ones, were automatically and systematically selected, and manually interpreted by referencing high-resolution images dated from 2009 to 2011 on Google Earth. The results show that the overall accuracy （OA） of four datasets ranges from 61.26 to 80.63%. GlobeLand30 dataset, with the highest accuracy, is the most accurate dataset for cropland classification. The cropland spatial agreement （mainly located in the plain ecotope of Shaanxi） and the non-cropland spatial agreement （sparsely distributed in the south and middle of Shaanxi） of the four datasets only makes up 33.96% of the whole province. FIROM-GC and GlobeLand30, obtaining the highest spatial agreement index of 62.40%, have the highest degree of spatial consistency. In terms of the absolute area, MODIS underestimates the cropland area, while GlobCover2009 significantly overestimates it. These findings are of value in revealing to which extent and on which aspect that these global land cover datasets may agree with each other at

关键词： land cover cropland classification assessment MODIS GlobCover2009 FROM-GC GlobeLand30

Endoscopic stenting and concurrent chemoradiotherapy for advanced esophageal cancer:A case-control study

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World Journal of Gastroenterology 2012年第12期18卷 1404-1409页

作者： Xiang-Jun Jiang Ming-Quan song Yong-Ning Xin yu-Qiang Gao Zi-yu Niu Zi-Bin Tian Department of Gastroenterology QingdaoMunicipal Hospital affiliated to Qingdao University Qingdao266011 Shandong Province China QingdaoKey Laboratory of Digestive Diseases Qingdao Municipal Hos-pital Qingdao 266011 Shandong Province China Department of Gastroenterology Affiliated Hospitalof Qingdao University Medical College Qingdao 266003 Shan-dong Province China

AIM:To evaluate the role of endoscopic stenting with or without concurrent 3-dimensional conformal chemoradiotherapy (3D-CRT) in patients with inoperable esophageal ***:Advanced esophageal cancer patients indicated for esophagectomy received esophageal stents.A part of patients completed 3D-CRT after *** was assessed by endoscopy and computed tomographic scan before and 4 wk after completion of the *** median survival,3D-CRT toxicity and complications were compared between 3D-CRT and control ***:From 1999 to 2008,99 consecutive patients with T3/T4 disease and unsuitable for esophagectomy were placed with esophageal ***-seven patients received 3D-CRT,while 36 patients treated withendoscopic stents alone were recruited as *** 3D-CRT treatment,the median tumor volume of 3D-CRT patients were reduced significantly from 43.7 ± 10.2 cm 3 to 28.8 ± 8.5 cm 3 (P < 0.05).The complete and partial response rate was 85.1%,and no response was 14.9%.After 3D-CRT,the incidence rate of T2 and T3 disease evident on CT scan increased to 78.4% while T4 decreased from 66.7% to 21.6% (P < 0.05).3DCRT Karnofsky Performance Status improved in 3D-CRT patients compared with the control group (P=0.031).3D-CRT patients had a longer survival than the control group (251.7 d vs 91.1 d,P < 0.05).And the median half-year survival rate in 3D-CRT group (91%) was higher than in the control group (50%,P < 0.05).The most common toxicity was leukocytopenia in the 3D-CRT group (46.7% vs 18.8%,P=0.008).The control group had a higher rate of restenosis than the 3D-CRT group (81.3% vs 9.0%,P < 0.05).The rate of nephrotoxicity was increased in 3D-CRT as compared with the control group (31.3% vs 15.6%,P < 0.05).CONCLUSION:3D-CRT can improve dysphagia in patients with inoperable esophageal carcinoma.3D-CRT combined with stenting results in better survival as compared with endoscopic stents used alone.

关键词： Esophageal Cancer Stents Chemoradiothe-rapy Three-dimensional imaging Case control study

M-FCN based sea-surface weak target detection

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1111-1118页

作者： PAN Meiyan SUN Jun YANG yuhao li Dasheng yu Junpeng The 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210039China Key Laboratory of IntelliSense Technology China Electronics Technology Group CorporationNanjing 210039China

This paper focuses on the sea-surface weak target detection based on memory-fully convolutional network(M-FCN)in strong sea ***,the constant false alarm rate(CFAR)detection method utilizes a low threshold with high probability of false alarm to detect sea-surface weak targets after non-coherent *** the detection threshold can generate a large number of false alarms while increasing the detection rate,and how to suppress a large number of false alarms is the key to improve the performance of weak target ***,the detection result of the low threshold is operated to construct the target matrix suitable for the size of fully convolutional networks and the convolution operator ***,the M-FCN architecture is designed to learn the different accumulation characteristics of the target and the sea clutter between different *** improving the detection performance,the historical multi-frame information is memorized by the network,and the end-to-end structure is established to detect sea-surface weak target *** results on measured data demonstrate that the M-FCN method outperforms the traditional track before detection(TBD)method and reduces false alarm tracks by 35.1%,which greatly improves the track quality.

关键词： sea-surface weak target detection memory-fully convolutional network(M-FCN) multi-frame information end-to-end