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Effects of Fe content on the microstructure and properties of CuN i10FeM n1 alloy tubes fabricated by HCCM horizontal continuous casting

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 449-457页

作者： yan-bin Jiang jun xu Xin-hua Liu Jian-xin Xie Key Laboratory for Advanced Materials Processing of the Ministry of Education University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology Beijing

Heating-cooling combined mold（HCCM） horizontal continuous casting technology developed by our research group was used to produce high axial columnar-grained CuN i10 FeM n1 alloy tubes with different Fe contents. The effects of Fe content（1.08wt%–2.01wt%） on the microstructure, segregation, and flushing corrosion resistance in simulated flowing seawater as well as the mechanical properties of the alloy tubes were investigated. The results show that when the Fe content is increased from 1.08wt% to 2.01wt%, the segregation degree of Ni and Fe elements increases, and the segregation coefficient of Ni and Fe elements falls from 0.92 to 0.70 and from 0.92 to 0.63, respectively. With increasing Fe content, the corrosion rate of the alloy decreases initially and then increases. When the Fe content is 1.83wt%, the corrosion rate approaches the minimum and dense, less-defect corrosion films, which contain rich Ni and Fe elements, form on the surface of the alloy; these films effectively protect the α-matrix and reduce the corrosion rate. When the Fe content is increased from 1.08wt% to 2.01wt%, the tensile strength of the alloy tube increases from 204 MPa to 236 MPa, while the elongation to failure changes slightly about 46%, indicating the excellent workability of the CuNi10FeMn1 alloy tubes.

关键词： copper nickel alloys iron content casting segregation mechanical properties corrosion resistance

Structure-directing Effect on Synthesis of Layered Aluminophosphates with Same Topology

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Chemical Research in Chinese Universities 2017年第4期33卷 513-519页

作者： WANG Aitian xu jun WANG Chao DENG Feng xu Ruren yan Wenfu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changehun 130012 P. R. China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 P. R. China

Three layered aluminophosphates（UiO-15, APDAP12-150 and APDAP-150） with same topology were crystallized from an initial mixture with a molar Composition of A1203：***2Os：5.5R：227HzO, where R is ethylene- diamine, 1,2-diaminopropane or 1,3-diaminopropane, respectively. The crystallization processes of UiO-15, APDAPI2-150 and APDAP-150 were investigated using solid-state NMR in combination with XRD and other cha- racterization techniques. The evolution of the coordination states of Al and P in the solid products was monitored, and the possible starting points of crystallization（core units） of UiO-15, APDAP12-150 and APDAP-150 were obtained and analyzed. The formation ofa trimer as well as a hexamer of aluminophosphate, a monomer of PO4 and a nonamer containing two three-membered rings is critical for the start of crystallization of UiO-15. The formation of a hexamer and a pentamer is critical for the start of crystallization of APDAP12-150. The formation of an A106 monomer and a pentamer containing a three-membered ring is critical for the start of crystallization ofAPDAP-150. The crystal water played a co-structure-directing role in the formation ofAPDAP-150.

关键词： Zeolite Aluminophosphate Templating effect Stnlcture-directing effect

Effect of organic amendment amount on soil nematode community structure and metabolic footprints in soybean phase of a soybean-maize rotation on Mollisols

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Pedosphere 2020年第4期30卷 544-554页

作者： Fengjuan PAN Xiaozeng HAN Na LI jun yan yanli xu National Observation Station of Hailun Agro-ecology System Key Laboratory of Mollisols AgroecologyNortheast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081(China)

It has been well documented that organic amendment affects soil nematode community ***,little is known about the effect of organic amendment amount on soil *** assess the effect of the amount of organic amendments on soil nematode community structure and metabolic activity,the community composition,abundance,and metabolic footprints of soil nematodes were determined in a long-term field experiment with various amounts of organic amendment in Northeast *** treatments included an unfertilized control(CK),chemical fertilizer without manure amendment(OM0),manure applied at 7.5 Mg ha^-1 plus chemical fertilizer(OM1),and manure applied at 22.5 Mg ha^-1 plus chemical fertilizer(OM2).A total of 46 nematode genera were *** with the largest amount of organic amendment had the smallest number of plant parasite genera(5),but a largest number of dominant genera(7).Soil nematodes,bacterivores,and fungivores were the most abundant in OM2,followed by OM1,and the lowest in OM0 and *** amendment increased the enrichment index(EI),and the large amount of organic amendment increased the metabolic footprints of bacterivore(Baf)and fungivore(Fuf)and enrichment footprint(Ef).The relationships between Baf(or Fuf)and the increases in soil organic carbon(?SOC)and total nitrogen(?TN)were stronger than those of bacterivore(or fungivore)abundance with?SOC and?TN,except for the relationship between bacterivore abundance and ?*** EI and Ef were positively correlated with ?SOC and ?*** findings suggest that the amount of organic amendment affects soil nematode activity and function at entry levels in soil food web,and that metabolic footprints of soil nematodes may be better indicators than their abundances in assessing their relationships with soil nutrients.

关键词： community composition ecosystem function enrichment footprint enrichment index metabolic activity soil food web trophic group

Influence of Fluoride Ions on the Structure-directing Effect of Organic Amine in the Synthesis of Aluminophosphate Open-frameworks

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Chemical Research in Chinese Universities 2017年第6期33卷 853-859页

作者： TIAN Ye xu jun WANG Zi DENG Feng xu Ruren yan Wenfu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 P R. China Jilin Province Product Quality Supervision Testing Institute Changchun 130012 P. R. China

The crystallization behavior of the initial mixture with the composition of Al2O3：4.0P2O5：3.0 diethylenetriamine（DETA）：xHF：153H2O was investigated at 180 ℃, where 0≤x≤3. If x≤1.8, three-dimensional openframework aluminophosphate AIPO-CJ31 was obtained. If 2 ≤x≤3, a chain-like aluminophosphate（1） was obtained. The crystallization process of both compounds was investigated by means of powder X-ray diffraction（XRD） and the concentrations of A1 and P in the liquid product during the crystallization process were analysed by means of induc- tively coupled plasma atomic emission spectroscopy（ICP-AES）. The evolution of the coordination state of A1, P and F during the crystallization was monitored with 27A1, 31p and 19F MAS NMR technique. The influence of the fluoride ions and the source of fluoride ions on the structure-directing effect of DETA was discussed. It was found that the fluoride ions changed the crystallization direction of the initial mixture, i.e., the structure-directing effect of DETA, via altering the distribution or micro-structure of the inorganic fragments.

关键词： Zeolite Aluminophosphate Open-framework Structure-directing effect Fluoride

Epitaxial Growth of Si(111)/Er2O3(111)Structure on Si(111)by Molecular Beam Epitaxy

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Chinese Physics Letters 2011年第3期28卷 176-179页

作者： xu Run TANG Min-yan ZHU yan-yan WANG Lin-jun School of Materials Science and Engineering Shanghai UniversityShanghai 200072 Department of Mathematics and Physics Shanghai University of Electric PowerShanghai 200090

The Si overlayers are grown by molecular beam epitaxy on atomically smllth Er_(2)O_(3)(111)films prepared on Si(111)*** crystalline Si overlayers are achieved and are evident due to the spot-like reflective high energy electron diffraction(RHEED)patterns and x-ray diffraction *** epitaxial relationship of the Si overlayer along the surface with respect to the orientation of Er_(2)O_(3)and the Si substrate is as follows:overgrown Si(111)//Er_(2)O_(3)(111)//Si(111).The rough surface of Si overlayers,as identified by both RHEED patterns and atomic force microscopy images,indicates a three-dimensional growth *** reason for this is based on the interfacial energy *** growth of Er_(2)O_(3)films on this rough Si overlayer leads to the polycrystalline nature of the topmost Er2O3 layer.

关键词： Si(111) Epitaxy reflective

多光谱法研究二氢杨梅素对胰脂肪酶的抑制作用

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光谱学与光谱分析 2025年第1期45卷 107-116页

作者：孟晓慧黄旭波夏张晨徐娟王衍彬程俊文杨柳贺亮浙江省森林资源生物与化学利用重点实验室浙江省林业科学研究院浙江杭州310023 浙江省特色中药资源保护与创新利用重点实验室浙江农林大学食品与健康学院浙江杭州311300

藤茶中主要黄酮类物质——二氢杨梅素(DMY)具有多种生物活性,而其降血脂机理鲜有报道。采用紫外光谱研究了DMY对胰脂肪酶(PL)的抑制作用,结合荧光光谱、同步荧光光谱、三维荧光光谱及分子对接模拟法研究了二者之间的相互作用及机理。紫... 详细信息

藤茶中主要黄酮类物质——二氢杨梅素(DMY)具有多种生物活性,而其降血脂机理鲜有报道。采用紫外光谱研究了DMY对胰脂肪酶(PL)的抑制作用,结合荧光光谱、同步荧光光谱、三维荧光光谱及分子对接模拟法研究了二者之间的相互作用及机理。紫外光谱测得DMY对PL的半抑制浓度为2.6×10^(-4)mol·L^(-1),表明其对PL具有较好的抑制作用,采用Lineweaver-Burk方程得出该抑制剂为竞争性作用,其抑制常数为6×10^(-4)mol·L^(-1);通过Stern-Volmer方程和静态猝灭双对数公式对293和310 K两者互作的荧光光谱计算,结果表明DMY能猝灭PL的自发荧光,荧光猝灭方式为静态猝灭,猝灭常数K_(SV)与温度负相关;结合常数K a与温度正相关,结合位点数n约为1,说明DMY与PL结合并形成稳定的配位复合物;采用Van't Hoff方程求出结合过程中的热力学参数ΔS=0.2014 J·mol^(-1)·K^(-1),ΔH=32.311 kJ·mol^(-1),ΔG小于0,表明两者通过疏水作用力自发结合且放热;由F rster非辐射能量转移理论计算出结合距离r=1.475 nm,说明DMY与PL结合生成复合物时发生了非辐射能量转移;同步荧光光谱结果表明,DMY与PL的相互作用对PL的二级构象发生了明显改变,主要作用于色氨酸(Tyr)附近。紫外光谱进一步揭示DMY可使PL发生π→π跃迁,导致其氨基酸残基的微环境变化;三维荧光光谱显示DMY可使PL两个特征峰(peak1,peak2)分别红移10和5 nm,荧光强度分别下降51.38%和41.93%,证实两者发生疏水作用后PL的微环境极性增大,构象改变;分子对接模拟结果表明,DMY结合位点位于PL中由PHE77、PHE215、TYR114、ILE209、PRO180氨基酸形成的疏水口袋内,其A环C5、B环C4′、C环C3、C环C O的-OH分别与氨基酸HIS263、TYR114、SER152、PHE215形成氢键,与氨基酸LRU213、GLU179、ALA178、THR78产生范德华力。实验数据有助于深入解DMY的降血脂分子作用机制,其独特的结构为天然抑制剂的药物合成和筛选提供了理论依据。

关键词：二氢杨梅素胰脂肪酶多光谱法分子对接模拟

Phytic acid-derived fabrication of ultra-small MoP nanoparticles for efficient CO methanation: Effects of P/Mo ratios

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Journal of Energy Chemistry 2020年第8期29卷 248-255,I0009页

作者： jun Zhao Zijia Yin Baowei Wang Zhenhua Li yan xu Xinbin Ma Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Molybdenum phosphide(MoP) catalyst has been widely applied in hydrogenation reactions, while the preparation of unsupported MoP catalysts with ultra-small size and large specific surface area(SBET) is still challenging. Herein, we have provided a facile method for preparing a series of MoP-x(x=P/Mo ratios ranging from 1 to 5) catalysts by pyrolyzing phytic acid(PA)-derived Mo complexes in a H2 atmosphere. The physicochemical properties and the catalytic activity of MoP catalysts were investigated. The results showed that the obtained MoP-5 catalyst had the largest SBETand exhibited ultra-small nanoparticle diameter of 3.6 nm, which ascribed to the chelation of PA and the confinement of deposited *** the content of PA increased, the synthetic mechanism of MoP was also affected, which led to the difference in the valence of surface Mo species. The characterization results further confirmed that Moδ+ sites in MoP catalysts are active sites for methanation reaction and its content on the surface of MoP-x catalysts determines the catalytic activity.

关键词： Molybdenum phosphide Phytic acid P/Mo ratios Ultra-small nanoparticle CO methanation

牛乳头状瘤病毒2型贵州株L2基因克隆及生物信息学分析

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中国兽药杂志 2017年第8期51卷 14-22页

作者：张海杨丽彦张军冯旭芳周碧君王开功文明程振涛王伟胡兴义贵州大学动物科学学院贵阳550025 贵州轻工职业技术学院贵阳550025 贵州省六盘水市动物卫生监督所贵州六盘水553001 贵州省德江县动物疫病预防控制中心贵州德江565200

为分析牛乳头状瘤病毒2型贵州株(BPV2-GZ01株)L2基因的分子特征,预测编码蛋白的生物学功能,对BPV2-GZ01株L2基因进行PCR扩增、克隆及序列测定,应用生物信息学相关软件及方法,对BPV2-GZ01株L2基因进行序列分析并对其编码蛋白进行二级结... 详细信息

为分析牛乳头状瘤病毒2型贵州株(BPV2-GZ01株)L2基因的分子特征,预测编码蛋白的生物学功能,对BPV2-GZ01株L2基因进行PCR扩增、克隆及序列测定,应用生物信息学相关软件及方法,对BPV2-GZ01株L2基因进行序列分析并对其编码蛋白进行二级结构、三级结构、B细胞表位、保守结构域、跨膜结构域和信号肽预测。结果显示,L2基因PCR扩增产物大小为1404 bp,编码467个氨基酸;与参考株BPV2株、BPV2-SW01株、BPV2-AKS01株、BPV13株、BPV1株相应序列核苷酸同源性分别为99.0%、99.7%、99.3%、83.9%和75.1%,氨基酸的同源性分别为98.9%、99.6%、99.4%、89.5%和82.7%;系统进化显示,BPV2-GZ01株L2基因与BPV2-SW01株亲缘关系最近;二级结构以无规则卷曲、β-折叠和α-螺旋区域所占比例较大,预测此蛋白可能存在B细胞优势抗原表位,无跨膜区域,无信号肽区域。本研究结果将为贵州省BPV核酸疫苗研究提供理论依据。

关键词：牛乳头状瘤病毒2型贵州株 L2基因生物信息学分析

Four-soliton solution and soliton interactions of the generalized coupled nonlinear Schrodinger equation

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Chinese Physics B 2020年第6期29卷 216-223页

作者： Li-jun Song Xiao-Ya xu yan Wang Department of Physics and Electronic Engineering Shanxi UniversityTaiyuan 030006China

Based on the generalized coupled nonlinear Schr¨odinger equation,we obtain the analytic four-bright–bright soliton solution by using the Hirota bilinear *** interactions among four solitons are also studied in *** results show that the interaction among four solitons mainly depends on the values of solution parameters;k1 and k2 mainly affect the two inboard solitons while k3 and k4 mainly affect the two outboard solitons;the pulse velocity and width mainly depend on the imaginary part of ki(i=1,2,3,4),while the pulse amplitude mainly depends on the real part of ki(i=1,2,3,4).

关键词： coupled nonlinear Schrodinger equation four-soliton solution soliton interaction