检索结果-南通市图书馆

Precise regulation of the phase transformation for pyrolusite during the reduction roasting process

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 81-90页

作者： Ruofeng Wang Peng gao shuai Yuan Yanjun Li Yingzhi Liu Cheng Huang School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-Local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China

The mechanism involved in the phase transformation process of pyrolusite (MnO_(2)) during roasting in a reducing atmosphere was systematically elucidated in this study,with the aim of effectively using low-grade complex manganese ore *** to single-factor experiment results,the roasted product with a divalent manganese (Mn^(2+)) distribution rate of 95.30% was obtained at a roasting time of 25 min,a roasting temperature of 700℃,a CO concentration of 20at%,and a total gas volume of 500 mL·min^(-1),in which the manganese was mainly in the form of manganosite (MnO).Scanning electron microscopy and Brunauer–Emmett–Teller theory demonstrated the microstructural evolution of the roasted product and the gradual reduction in the pyrolusite ore from the surface to the core Thermodynamic calculations,X-ray photoelectron spectroscopy,and X-ray diffractometry analyses determined that the phase transformation of pyrolusite followed the order of MnO_(2)→Mn_(2)O_(3)→Mn_(3)O_(4)→MnO phase by phase,and the reduction of manganese oxides in each valence state proceeded simultaneously.

关键词： pyrolusite phase transformation reduction roasting microstructural evolution reaction mechanism

Hydrogen-based mineral phase transformation mechanism investigation of pyrolusite ore

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals, Metallurgy and Materials 2024年第11期31卷 2445-2457页

作者： Wang, Ruofeng Yuan, shuai Li, Yanjun gao, Peng Li, Ru School of Resources and Civil Engineering Northeastern University Shenyang China National-local Joint Engineering Research Center of High-efficient exploitation technology for Refractory Iron Ore Resources Shenyang China

Pyrolusite comprises the foremost manganese oxides and is a major source of manganese production. An innovative hydrogen-based mineral phase transformation technology to pyrolusite was proposed, where a 96.44% distribution rate of divalent manganese (Mn2+) was observed at an optimal roasting temperature of 650°C, a roasting time of 25 min, and an H2 concentration of 20vol%; under these conditions. The manganese predominantly existed in the form of manganosite. This study investigated the generation mechanism of manganosite based on the reduction kinetics, phase transformation, and structural evolution of pyrolusite and revealed that high temperature improved the distribution rate, and the optimal kinetic model for the reaction was the random nucleation and growth model (reaction order, n = 3/2) with an activation energy (Ea) of 24.119 kJ·mol−1. Throughout the mineral phase transformation, manganese oxide from the outer layer of particles moves inward to the core. In addition, pyrolusite follows the reduction sequence of MnO2 → Mn2O3 → Mn3O4 → MnO, and the reduction of manganese oxides in each valence state simultaneously proceeds. These findings provide significant insight into the efficient and clean utilization of pyrolusite.

关键词： reduction pyrolusite phase transformation microstructural evolution

A systematic survey of PRMT interactomes reveals the key roles of arginine methylation in the global control of RNA splicing and translation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2021年第13期66卷 1342-1357,M0004页

作者： Huan-Huan Wei Xiao-Juan Fan Yue Hu Xiao-Xu Tian Meng Guo Miao-Wei Mao Zhao-Yuan Fang Ping Wu shuai-xin gao Chao Peng Yun Yang Zefeng Wang CAS Key Laboratory of Computational Biology Bio-Med Big Data CenterShanghai Institute of Nutrition and HealthCAS Center for Excellence in Molecular Cell ScienceUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China National Facility for Protein Science in Shanghai Zhang-Jiang LabShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Xijing Hospital of Digestive Diseases Fourth Military Medical UniversityXi’an 710000China

Thousands of proteins undergo arginine methylation,a widespread post-translational modification catalyzed by several protein arginine methyltransferases(PRMTs).However,global understanding of their biological functions is limited due to the lack of a complete picture of the catalytic network for each ***,we systematically identified interacting proteins for all human PRMTs and demonstrated their functional importance in mRNA splicing and *** demonstrated significant overlapping of interactomes of human PRMTs with the known methylarginine-containing *** PRMTs are functionally redundant with a high degree of overlap in their substrates and high similarities between their putative methylation ***,RNA-binding proteins involved in regulating RNA splicing and translation contain highly enriched arginine methylation ***,inhibition of PRMTs globally alternates alternative splicing(AS)and suppresses *** particular,ribosomal proteins are extensively modified with methylarginine,and mutations in their methylation sites suppress ribosome assembly,translation,and eventually cell ***,our study provides a global view of different PRMT networks and uncovers critical functions of arginine methylation in regulating mRNA splicing and translation.

关键词： Post-translational modification Protein arginine methyltransferase RNA-binding protein Ribosomal proteins Alternative splicing mRNA translation

Reconstruction of Postinfarcted Cardiac Functions Through Injection of Tanshinone IIA@ Reactive Oxygen Species-Sensitive Microspheres Encapsulated in a Thermoreversible Hydrogel

在线全文

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第2期7卷 191-203页

作者： Ling Yu Yubin Liang Lei gao Peipei Chen Zhiqiang Yu Minzhou Zhang Aleksander Hinek shuai Mao Second Clinical College Guangzhou University of Chinese Medicine Department of Critical Care Medicine Guangdong Provincial Hospital of Chinese Medicine Guangdong Provincial Branch of National Clinical Research Centre for Chinese Medicine Cardiology Department of Radiation Medicine and Applied Sciences University of California San Diego Department of Laboratory Medicine Dongguan Institute of Clinical Cancer Research Affiliated Dongguan Hospital Southern Medical University Translational Medicine Hospital for Sick Children

Myocardial damage resulting from acute myocardial infarction often leads to progressive heart failure and sudden death, highlighting the urgent clinical need for effective therapies. Recently, tanshinone IIA has been identified as a promising therapeutic agent for myocardial infarction. However, efficient delivery remains a major issue that limits clinical translation. To address this problem, an injectable thermosensitive poly(lactic acid-co-glycolic acid)-block-poly(ethylene glycol)-block-poly(lactic acid-co-glycolic acid) gel(PLGA-PEG-PLGA) system encapsulating tanshinone IIA-loaded reactive oxygen species-sensitive microspheres(Gel-MS/tanshinone IIA) has been designed and synthesized in this study. The thermosensitive hydrogel exhibits good mechanical properties after reaching body temperature. Microspheres initially immobilized by the gel exhibit excellent reactive oxygen speciestriggered release properties in a high-reactive oxygen species environment after myocardial infarction onset. As a result, encapsulated tanshinone IIA is effectively released into the infarcted myocardium, where it exerts local antipyroptotic and anti-inflammatory effects. Importantly, the combined advantages of this technique contribute to the mitigation of left ventricular remodeling and the restoration of cardiac function following tanshinone ***, this novel, precision-guided intra-tissue therapeutic system allows for customized local release of tanshinone IIA, presenting a promising alternative treatment strategy aimed at inducing beneficial ventricular remodeling in the post-infarct heart.

关键词： myocardial infarction ROS-sensitive polymer tanshinone IIA thermoreversible hydrogel ventricular remodeling

Effect of TiO_(2) addition on microstructures and properties of Mgo-Cao refractory aggregates

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1547-1554页

作者： shuai Zhang Jing-ran Wang Yuan-gao Li Feng-you Li Wen Yan Hui-ying Shi The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Joint International Research Laboratory of Refractories and Metallurgy Wuhan 430081HubeiChina Shanxi Luweibao Taigang Refractory Co. Ltd.Taiyuan 030003ShanxiChina

MgO-CaO(40 wt.%CaO)refractory aggregates were prepared using the calcined dolomite and light-burned magnesia fine powder as raw materials and TiO_(2) as *** effect of TiO_(2) on their phase composition,microstructures and properties was investigated by X-ray diffraction and scanning electron *** properties such as bulk density,apparent porosity,relative aggregate tube strength and hydration resistance were also *** results showed that the CaTiO_(3) generated by the reaction between CaO and TiO_(2) was distributed around the CaO grain boundaries and intermittently distributed with MgO,which formed an isolation layer around CaO and greatly improved the hydration ***,the introduction of TiO_(2) promoted sintering and increased the grain size,further improving the strengths and hydration resistance of the *** addition,the most significant enhancement in the hydration resistance and strengths of the samples was achieved when 1.0-2.0 wt.%TiO_(2) was *** this case,the relative strength of aggregate increased from 33.3% to 37.3%-43.1%,and the mass gain after the hydration test decreased from 3.13% to 1.26%-1.45%.

关键词： MgO-CaO refractory aggregate TiO_(2)addition Phase composition Microstructure Hydration resistance

Performance evaluation of new epoxy resin-based composite phase change materials and their asphalt mixture

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 Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 507-522页

作者： Yuchao gao Jiao Jin shuai Liu Yinfei Du Guoping Qian Jie Mao Yongqiang Zhu School of Traffic and Transportation Engineering Changsha University of Science and TechnologyChangsha 410114China School of Civil Engineering Central South UniversityChangsha 410075China Guangdong Guanyue Highway and Bridge Co. Ltd.Guangzhou 511452China

In recent years,the temperature-adjusted asphalt pavement has been an extensive concern by scholars in various countries,and this pavement can reduce temperaturerelated *** this study,the shaped composite phase change materials(CPCMs)were successfully synthesized by two processes,which are vacuum impregnation and epoxy ***,the applicability of CPCMs in asphalt mixtures was evaluated by microscopic characterization,chemical compatibility,thermal properties,durability,and leakage ***,CPCMs were applied to the asphalt mixture to evaluate its temperatureadjusted characteristics and pavement ***,the performance of the temperature-adjusted asphalt mixture was analyzed by integrating all *** research shows that the prepared CPCMs have excellent thermal properties and durability,the phase transition temperature is 48.93℃,and the phase transition enthalpy is 106.5 J/g,which fully meets the requirements for use in *** temperature-adjusted asphalt mixture could alleviate the occurrence of extreme temperature,which was 4.9℃lower than the conventional *** pavement performance of the temperatureadjusted asphalt mixture can meet the specified standards for humid *** the factors,the recommended amount of CPCMs is 1.5%.The research results provide a basis for the promotion of temperature-adjusted asphalt pavement and effectively support the development of pavement engineering technology.

关键词： Pavement engineering Temperature-adjusted asphalt mixture Phase change materials Thermal performance

Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： Xiao-lin Sun Han-jie Guo Jing Guo Fei Wang Dong Xu gao-yang Song shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

Pentacoordinate Phosphoranes as Versatile Reagents in Fluoroalkylation Reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第1期6卷 165-176页

作者： Huanhuan Song Weihao Li Xiaoying Wang Kaiteng Wang Jingwen Li shuai Liu Pin gao xin-Hua Duan Jinbo Hu Mingyou Hu School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Key Laboratory of Sustainable Energy Material ChemistryXi’an Jiaotong UniversityXi’an 710049 Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032

A general method for the synthesis of bench-stable bis(difluoromethyl)pentacoordinate phosphoranes has been *** reaction is rapid,operationally simple,and easily *** pentacoordinate phosphoranes can generate both difluoromethyl radical(·CF_(2)H)and difluorocarbene(:CF_(2))***,a variety of fluoroalkylation transformations havebeen achieved by·CF_(2)H,such asoxidativedifluoromethylation of electron-deficient heterocycles,nickel/photoredox dual-catalyzed difluoromethylation of aryl bromides,and photoredox difluoromethylation of alkenes,or by:CF_(2),such as gem-difluorocyclopropanation of alkenes,base-promoted difluoromethylation of heteroatom nucleophiles,Pd-catalyzed difluoromethylation of arylboronic acids,and Cu-mediated trifluoromethylation of aryl iodides(via:CF_(2) and recombined CF_(3)-).These fluoroalkylation methods have been successfully applied to late-stage fluoroalkylation of drugs and drug-like molecules.

关键词： pentacoordinate phosphorane difluoromethyl radical difluorocarbene difluoromethylation fluoroalkylation

Highly crystallization-induced emissive luminophores with mechanoluminescent features for two-photon harvesting fluorescence imaging and latent fingerprint identification

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 6475-6482页

作者： Jian Lu Juan gao Rui-Xuan Qian shuai-Hua Wang Fa-Kun Zheng Guo-Cong Guo Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense *** fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and ***,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper ***,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication *** with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh ***,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)*** novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.

关键词： crystallization-induced emission fluorescence imaging two-photon absorption fingerprint recognition mechanoluminescence