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A TRUST-REGION METHOD FOR SOLVING TRUNCATED COMPLEX SINGULAR VALUE DECOMPOSITION

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Journal of Computational Mathematics 2024年第4期42卷 999-1031页

作者： Jiaofen Li Lingchang kong Xuefeng Duan Xuelin Zhou Qilun Luo School of Mathematics and Computing Science Guangxi Colleges and Universities Key Laboratory of Data Analysis and ComputationGuangxi Key Laboratory of Automatic Detecting Technology and InstrumentsGuilin University of Electronic TechnologyCenter for Applied Mathematics of Guangxi(GUET)Guilin 541004China School of Mathematical Sciences South China Normal UniversityGuangzhou 510000China School of Mathematics and Computing Science Guilin University of Electronic TechnologyGuilin 541004China School of Mathematics and Computing Science Guangxi Colleges and Universities Key Laboratory of Data Analysis and ComputationGuilin University of Electronic TechnologyCenter for Applied Mathematics of Guangxi(GUET)Guilin 541004China School of Mathematics and Statistics Yunan UniversityKunming 650000China

The truncated singular value decomposition has been widely used in many areas of science including engineering,and statistics,*** this paper,the original truncated complex singular value decomposition problem is formulated as a Riemannian optimiza-tion problem on a product of two complex Stiefel manifolds,a practical algorithm based on the generic Riemannian trust-region method of Absil et *** presented to solve the underlying problem,which enjoys the global convergence and local superlinear conver-gence *** experiments are provided to illustrate the efficiency of the proposed *** with some classical Riemannian gradient-type methods,the existing Riemannian version of limited-memory BFGS algorithms in the MATLAB toolbox Manopt and the Riemannian manifold optimization library ROPTLIB,and some latest infeasible methods for solving manifold optimization problems,are also provided to show the merits of the proposed approach.

关键词： Truncated singular value decomposition Riemannian optimization Trust-region method

Dealuminated Hβ zeolite for selective conversion of fructose to furfural and formic acid

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Green Energy & Environment 2024年第2期9卷 311-320页

作者： Rui Li Qixuan Lin Junli Ren Xiaobao Yang Yingxiong Wang Lingzhao kong State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510640China Institute of Coal Chemistry Chinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201210China School of Environmental Science and Technology Suzhou University of Science and Technology Suzhou Jiangsu215009China

The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural using Hβ zeolite modified by organic acids for dealuminization to regulate its textural and acidic properties. It was found that citric acid-dealuminized Hβ zeolite possessed high specific surface areas, wide channels and high Brønsted acid amount, which facilitated the selective conversion of fructose to furfural with a maximum yield of 76.2% at433 K for 1 h in the γ-butyrolactone(GBL)-H_(2)O system, as well as the concomitant formation of 83.0% formic acid. The^(13)C-isotope labelling experiments and the mechanism revealed that the selective cleavage of C1–C2 or C5–C6 bond on fructose was firstly occurred to form pentose or C5 intermediate by weak Brønsted acid, which was then dehydrated to furfural by strong Brønsted acid. Also this dealuminized Hβ catalyst showed the great recycling performance and was active for the conversion of glucose and mannose.

关键词： Fructose Dealuminated-Hb zeolite Selective conversion Furfural

Mechanisms underlying key agronomic traits and implications for molecular breeding in soybean

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Journal of Genetics and Genomics 2024年第4期51卷 379-393页

作者： Chao Fang Haiping Du Lingshuang Wang Baohui Liu Fanjiang kong Guangdong Key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life SciencesGuangzhou UniversityGuangzhouGuangdong 510006China

Soybean(Glycine max[L.]Merr.)is an important crop that provides protein and vegetable oil for human *** soybean is a photoperiod-sensitive crop,its cultivation and yield are limited by the photoperiodic conditions in the *** contrast to other major crops,soybean has a special plant architecture and a special symbiotic nitrogen fixation system,representing two unique breeding ***,flowering time,plant architecture,and symbiotic nitrogen fixation are three critical or unique yielddetermining *** review summarizes the progress made in our understanding of these three critical yield-determining factors in ***,we propose potential research directions to increase soybean production,discuss the application of genomics and genomic-assisted breeding,and explore research directions to address future challenges,particularly those posed by global climate changes.

关键词： Soybean Grain yield Flowering time Plant architecture Nodulation Symbiotic nitrogen fixation Genome study

Numerical investigation of sinusoidal pulsating gas intake to intensify the gas-slag momentum transfer in the top-blown smelting furnace

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 301-314页

作者： Zhanghao Wan Shiliang Yang Desong kong Dongbo Li Jianhang Hu Hua Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Southwest Copper Branch Yunnan Copper Co.Ltd.Kunming 650102China

The variation characteristics of bubble morphology and the thermal-physical properties of bubble boundary in the top-blown smelting furnace were explored by means of the computational fluid dynamics *** essential aspects of the fluid phase(e.g.,splashing volume,dead zone of copper slag,and gas penetration depth)were explored together with the effect of sinusoidal pulsating gas intake on the momentum-transfer performance between *** results illustrated that two relatively larger vortices and two smaller vortices appear in the bubble waist and below the lance,*** expansion of larger ones as well as the shrinking of smaller ones combine to cause the contraction of the bubble *** to the results of the case with a fixed gas injection velocity(V_(g)=58 m/s),the splashing volume and dead zone volume of the slag under the V_(g)=58+10sin(2πt)condition are reduced by 24.9%and 23.5%,respectively,where t represents the instant *** penetration depth and slag motion velocity of the latter are 1.03 and 1.31 times high-er than those of the former,respectively.

关键词： top-blown smelting furnace pulsed flow volume of fluid penetration depth splashing volume

Impacts of agri-food e-commerce on traditional wholesale industry:Evidence from China

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Journal of Integrative Agriculture 2024年第4期23卷 1409-1428页

作者： Ruyi Yang Jifang Liu Shanshan Cao Wei Sun Fantao kong Institute of Agricultural Information Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Special Animal and Plant Sciences Chinese Academy of Agricultural SciencesChangchun 130112China

Rapidly expanding studies investigate the effects of e-commerce on company operations in the retail ***,the interaction between agri-food e-commerce(AEC)and the traditional agri-food wholesale industry(AWI)has not received enough attention in the existing *** on the provincial panel data from 2013 to 2020 in China,this paper examines the effect of AEC on AWI,comprising three dimensions:digitalization(DIGITAL),agrifood e-commerce infrastructure and supporting services(AECI),and agri-food e-commerce economy(AECE).First,AWI and AEC are measured using an entropy-based combination of *** results indicate that for China as a whole,AWI has remained practically unchanged,whereas AEC exhibits a significant rising ***,the findings of the fixed-effect regression reveal that DIGITAL and AECE tend to raise AWI,whereas AECI negatively affects ***,threshold regression results indicate that AECI tends to diminish AWI with three-stage inhibitory intensity,which manifests as a first increase and then a drop in the inhibition *** results suggest that with the introduction of e-commerce for agricultural product circulation,digital development will have catfish effects that tend to stimulate the vitality of the conventional wholesale industry and promote technical ***,the traditional wholesale industry benefits financially from e-commerce even while it diverts part of the traditional wholesale circulation for agricultural products.

关键词： agri-food e-commerce traditional wholesale industry panel threshold model dual-channel circulation

Remarkable enhancement of gas selectivity on organosilica hybrid membranes using urea-modulated metal-organic framework nanoparticles

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 83-92页

作者： Yayun Zhao Dechuan Zhao Chunlong kong Yichao Lin Xuezhen Wang Liang Chen Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Collaboration Innovation Center for Tissue Repair Material Engineering Technology China West Normal UniversityNanchong 637009China

Metal-organic framework/organosilica hybrid membranes on tubular ceramic substrates have shown great potential for the implementation of membrane technology in practical gas separation projects due to their higher permeance compared to commercial ***,the selectivities of the reported membranes are ***,we have incorporated urea-modulated metal-organic frameworks into organosilica membranes to greatly enhance its separation *** urea-modulated metal-organic frameworks exhibit less-defined edges of crystallographic facets and high defect *** can be well-dispersed in the organosilica layer,which substantially suppresses the interfacial defects between metal-organic frameworks and organosilica,which is beneficial for improving the selectivity of membranes for gas *** results have shown that the enhanced ideal selectivity of H_(2)/CH_(4) was 165 and that of CO_(2)/CH_(4) was 43,with H_(2) permeance of about 1.25×10^(−6) mol·m^(−2)·s^(−1)·Pa^(−1) and CO_(2) permeance of 3.27×10^(−7) mol·m^(−2)·s^(−1)·Pa^(−1) at 0.2 MPa and 25℃.In conclusion,the high level of hybrid membranes can be used to separate H_(2)(or CO_(2))from the binary gas mixture H_(2)/CH_(4)(or CO_(2)/CH_(4)),which is important for gas separation in practical ***,the simple and feasible modulation of metal-organic framework is a promising strategy to tune different metal-organic frameworks for membranes according to the actual demands.

关键词： ZIF-8 nanocrystals urea organosilica hybrid membrane enhanced separation performance

Impact of H_(2)S on Hg^(0)capture performance over nitrogen-doped carbon microsphere sorbent:experimental and theoretical insights

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 89-100页

作者： Guopei Zhang Xiaoyang Zhang Xiangwen Xing Xiangru kong Lin Cui Dong Yong National Engineering Laboratory for Reducing Emissions from Coal Combustion Shandong UniversityJinan250061China Bingtuan Energy Development Institute Shihezi UniversityShihezi832000China

A nitrogen-doped carbon microsphere sorbent with a hierarchical porous structure was synthesized via aggregation-hydrothermal *** Hg^(0)adsorption performance of the nitrogen-doped carbon microsphere sorbent was tested and compared with that of the coconut shell activated carbon prepared in the *** effect of H_(2)S on Hg^(0)adsorption was also *** nitrogen-doped carbon microsphere sorbent exhibited superior mercury removal performance compared with that of coconut shell activated *** the absence of H_(2)S at a low temperature(≤100℃),the Hg^(0)removal efficiency of the nitrogen-doped carbon microsphere sorbent exceeded 90%.This value is significantly higher than that of coconut shell activated carbon,which is approximately 45%.H_(2)S significantly enhanced the Hg^(0)removal performance of the nitrogen-doped carbon microsphere sorbent at higher temperatures(100–180℃).The hierarchical porous structure facilitated the diffusion and adsorption of H_(2)S and Hg^(0),while the nitrogen-containing active sites significantly improved the adsorption and dissociation capabilities of H_(2)S,contributing to the generation of more active sulfur species on the surface of the nitrogen-doped carbon microsphere *** formation of active sulfur species and HgS on the sorbent surface was further confirmed using X-ray photoelectron spectroscopy and Hg^(0)temperature-programmed desorption *** functional theory was employed to elucidate the adsorption and transformation of Hg^(0)on the sorbent surface.H_(2)S adsorbed and dissociated on the sorbent surface,generating active sulfur species that reacted with gaseous Hg^(0)to form HgS.

关键词： nitrogen-doped carbon microsphere H_(2)S Hg^(0)removal adsorption mechanism

The risk factors and threshold level of subchronic inhalation exposure of reclaimed water

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Journal of Environmental Sciences 2024年第3期137卷 639-650页

作者： Jiayang kong Yun Lu Yunru Ren Menghao Chen Gang Liu Liangliang Shi State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute *** exposure has also been shown to induce infammatory responses with visible tissue ***,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is *** this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed ***,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A ***,infammation persisted after a 4-week recovery *** calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/***,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed *** threshold level of endotoxin was lower than that in most non-potable reclaimed *** findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.

关键词： Reclaimed water Inhalation exposure Risk factor Threshold Infammation Endotoxin

Combined proteomic and metabolomic studies on the liver of Amur sturgeon Acipenser schrenckii under titanium dioxide nanoparticle exposure

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Journal of Oceanology and Limnology 2024年第3期42卷 1001-1015页

作者： Zhou ZHOU Ting LIU Jie kong Zhenxing ZHAO Junquan ZHU Key Laboratory of Aquacultural Biotechnology Ministry of Educationand Key Laboratory of Marine Biotechnology of Zhejiang ProvinceCollege of Marine SciencesNingbo UniversityNingbo 315000China Guizhou Fisheries Research Institute Guizhou Academy of Agriculture SciencesGuiyang 550000China

Nanomaterials,particularly titanium dioxide nanoparticles(TiO_(2)-NPs),are extensively utilized across various ***,their environmental release has raised concerns regarding their potential ecological and environmental *** reproductive toxicity of TiO_(2)-NPs in fish species has attracted considerable attention,yet conflicting research outcomes have been *** investigated the effects of TiO_(2)-NPs exposure on the liver of juvenile Amur sturgeon Acipenser schrenckii using label-free proteomic and untargeted metabolomic *** experiment included a control group and three groups exposed to different concentrations of TiO_(2)-NPs(low,TL;medium,TM;high,TH).Compared to the control group,9,19,and 25 proteins and 35,73,and 158 metabolites were differentially expressed in the TH,TM,and TL TiO_(2)-NP-exposed groups,*** differentially expressed genes(DEGs)were enriched in the Kyoto Encyclopedia for Genes and Genomes(KEGG)pathways related to glycolysis and ***,among the 126 correlated proteins,the most enriched pathways were associated with endocytosis and protein processing in the endoplasmic ***,syringic acid was significantly downregulated across all three TiO_(2)-NP-exposed *** obtain a comprehensive overview of the TiO_(2)-NP-induced expression changes,a co-regulated network of proteins and metabolites associated with TiO_(2)-NPs exposure was *** to TiO_(2)-NPs led to enrichment and alteration of pathways related to immune responses,including endocytosis,protein processing in the endoplasmic reticulum,and peroxisome proliferator-activated receptor(PPAR)*** conclusion,our findings indicate that exposure to TiO_(2)-NPs might disrupt glucose metabolism and induce immune responses,thus contributing to our understanding of the environmental impacts of nanomaterials and highlighting the need for further research and development of potential mitigation strategies.

关键词： TiO_(2)-nanoparticle exposure proteomics metabolomics glucose metabolism immune response