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Influence of pH, Heat and Enzymatic Treatments on the Activity of Antibacterial Substance in MRS and Milk Media Produced by Lactobacillus fermentum F6

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Agricultural Sciences in China 2010年第6期9卷 911-920页

作者： zhang yong LIU yong BAO Yan zhang He-ping Key Laboratory of Dairy Biotechnology and Engineering Ministry of Education/Department of Food Science and Engineering InnerMongolia Agricultural University Hohhot 010018 P.R. China

This study aimed to investigate the influence of pH,heat and enzymatic treatments on the activity of antibacterial substance in MRS,skim soy milk and bovine milk media fermented by a potential probiotic Lactobacillus fermentum *** antibacterial activity of the culture supernatant of *** F6 was tested against a wide range of Gram-positive and Gram-negative pathogenic bacteria including Staphylococcus aureus,Escherichia coli,Listeria monocytogenes,Salmonella typhimurium,and Shigella *** antibacterial activities were detected in MRS and milk but not in soy *** presumed that three kinds of probable components including organic acids,heat-stable and heat-labile proteinaceous compounds were involved in antibacterial activity of fermented MRS and *** influence of acids on antibacterial activity was pH-dependent and this effect multiplied with thermal treatments seemed *** analyses showed various significant differences of antibacterial activity among five pathogens were observed in pH and heat *** untreated fermented milk showed higher inhibitory activity to Gram-positive pathogenic bacteria than Gram-negative bacteria （P 〈 0.05）,indicating antibacterial substances of fermented milk are greatly different from fermented *** accurate stimulated gastrointestinal transit showed antibacterial substances would have no influence on intestinal *** range of antibacterial substances from pH 2.0 to 6.0 can be potentially used as food biopreservatives and alternative therapeutics.

关键词： Lactobacillusfermentum F6 antibacterial activity pH thermal treatments enzymatic effect

Dynamics of Spiral Wave Tip in Excitable Media with Gradient Parameter

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Communications in Theoretical Physics 2009年第7期52卷 173-179页

作者： DENG Bin-Wen zhang Guo-yong CHEN yong Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

Using a Barkley model as an example, we study spirM waves and spiral tips in a gradient excitable medium. The gradient distribution of parameters is introduced to depict the inhomogeneous medium. It is found that the parameter fluctuations play an important role in the morphology of spiral pattern and the movements of spiral tips. For varied gradient parameters, it is observed that there exist three kinds of spiral behaviors, stable rotation, rebound of spiral tip from the boundary, and spiral breakup.

关键词： spiral wave spatial gradient Barkley model

Soil Wetting Patterns and Water Distribution as Affected by Irrigation for Uncropped Ridges and Furrows

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Pedosphere 2015年第3期25卷 468-477页

作者： zhang yong-yong ZHAO Xi-Ning WU Pu-Te Linze Inland River Basin Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Key Laboratory of Eco-hydrology of Inland River Basin Chinese Academy of Sciences Institute of Water Saving Agriculture in Arid regions of China Northwest A&F University

The ridge-furrow tillage combined with furrow irrigation is being more widely applied and has been shown to be effective in the Loess Plateau of China. Accurate characterization of water infiltration behavior under ridge-furrow irrigation could provide guidelines and criteria for future irrigation system design and operation. Our objective was to investigate soil water behavior during ponding infiltration in a cross-sectional ridge-furrow configuration. Soil water movement within three different soil textures was tested by tracking the spatial and temporal soil water content(SWC) variations in a soil chamber. The two-dimensional transient flow initially transferred rapidly, but gradually decreased with elapsed infiltration time, approaching a stable flow after 90 min. A technical parameter equation incorporating the Philip equation was developed using the water balance method to accurately predict total applied water volume(TAWV). The wetting patterns moved outward in an elliptical shape. The wetted lateral and downward distances fitted using equations accounted for capillary and gravitational driving forces in variably wetted soil media. Increasing initial SWC resulted in an increase in wetted soil volume, which can also be caused by decreasing bulk density in a homogeneous soil. Higher water level produced greater wetted lateral distance and more irrigation uniformity. The wetted lateral distance was almost identical to the wetted depth in silty clay loam soil; hence ridge-furrow irrigation should be implemented in such finer-textured soils. The wetted soil volume differed markedly among different soil textures(hydraulic properties), demonstrating that these properties can largely determine soil water spreading patterns and distribution.

关键词： infiltration ridge-furrow tillage soil texture soil water content technical parameter equation wetted soil volume

Simulation of Gas Flow Field in Laval Nozzle and Straight Nozzle for Powder Metallurgy and Spray Forming

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Journal of Iron and Steel Research International 2008年第6期15卷 44-47页

作者： LI Zheng-dong zhang Guo-qing LI Zhou zhang yong XU Wen-yong National Key Laboratory of High Temperature Structural Materials Beijing Institute of Aeronautical Materials Beijing 100095 China

Gas flow field in nozzles and out of nozzles was calculated for Laval orifice and straight orifice nozzles. The results showed that the flow generated by the Laval nozzle had a higher exit velocity in the vicinity of the nozzle, in comparison with that of the straight nozzle, that is to say, a Laval nozzle was more efficient than a straight one in disintegrating the melt stream and was apt to produce finer powders. The flow generated by the Laval nozzle was less convergent and the velocity gradient along the radial direction was more moderate than that of a straight nozzle, which could contribute to a broad distribution of melt particles. According to their flow characteristics, the Laval nozzle was reckoned as a better choice of producing larger spray-formed billets.

关键词： numerical simulation computational fluid dynamics gas flow field atomization nozzle

Dynamics of CD4~+CD25~+ T Cells in Spleens and Mesenteric Lymph Nodes of Mice Infected with Schistosoma japonicum

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 299-304页

作者： Xiao-Ping CAI Hui zhang yong-Chen zhang yong WANG Chuan SU Min-Jun JI Hai-Wei WU Xiang ZHU Zhao-Song zhang Guan-Ling WU Department of Pathogenic Biology,Jiangsu Province Key Laboratoly of Modern Pathogenic Biology,Nanjing Medical University,Nanjing 210029,China Department of Pathogenic Biology Jiangsu Province Key Laboratory of Modern Pathogenic Biology Nanjing Medical UniversityNanjing 210029 China

CD4~+CD25~+T cells play a major role in modulating immune response,but few reports havebeen published about ***,we investigated the changes in CD4~+CD25~+T cell populations inspleens and mesenteric lymph nodes of mice infected with Schistosoma *** proportions ofCD4~+CD25~+T cells in total CD4~+T cells were analyzed by flow ***25 and Foxp3 expression wasmeasured by real-time quantitative polymerase chain *** suppressive activities of CD4~+CD25~+Tcells were detected by in vitro proliferation of *** showed that the percentage of CD4~+CD25~+T cells was the same as controls 3 weeks *** the acute stage of infection,the percentagedecreased ***,at the chronic stage of infection,it rebounded to normal levels or *** expression of the CD25 and Foxp3 showed gradual increase along with the infection *** experiment also showed the strong suppressive effect of CD4~+CD25~+T cells,isolated during the chronicstage,on proliferation of the CD25~-*** is the first time that the dynamics of CD4~+CD25~+T cellpopulations was demonstrated in mice infected with *** conclusion,our data indicated thatCD4~+CD25~+cells might be involved in the immune modulation during *** infection,which en-hances current knowledge of the mechanisms of the immuno-downregulation and re-infection inschistosomiasis.

关键词： Schistosoma japonicum CD4~+CD25~+ T cell chronic infection Foxp3

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life Sciences 2025年第1期68卷 272-283页

作者： Yuwei Hua Yizhi zhang Zhenming Guo Shan Bian yong zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

关键词： spatial transcriptome histological images spatial resolution enhancement

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： yong Hou Shuo zhang Jie Dang Jia Guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang Chenyang zhang Linlin Wu Wei Sun Hongliang zhang Jianhua Chen yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei Huijie zhang Jian Yang Jia Ran Jiqiang Ning Haiyan Wang yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of Chemistry Zhejiang Normal University Jinhua Advanced Research Institute Department of Optical Science and Engineering Fudan University College of Chemistry and Materials Engineering Zhejiang A&F University

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF) has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA), but there still remain problems such as limited yield, short cycle life,and ambiguous reaction mechanism. Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF, a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking. We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA, particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts, including heterointerface construction, defect engineering,single-atom engineering, and in situ reconstruction. Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated, and challenges and future directions of electrochemical oxidation of HMF are also prospected. This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Structural design