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定量核磁共振磷谱同时测定浓维磷糖浆中甘油磷酸钠和磷酸的含量

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分析化学 2024年第7期52卷 1020-1027页

作者：屠相土李俊雷虹徐玲萍曾茂法台州市食品药品检验研究院

建立了定量核磁共振磷谱法(31P-q NMR)同时测定浓维磷糖浆中α-甘油磷酸钠、β-甘油磷酸钠和磷酸含量的方法。考察了q NMR实验条件对测定结果的影响，选择六甲基磷酰三胺为内标、20%重水溶液（V/V）为溶剂，选择zgig脉冲序列、延迟时间3... 详细信息

建立了定量核磁共振磷谱法(31P-q NMR)同时测定浓维磷糖浆中α-甘油磷酸钠、β-甘油磷酸钠和磷酸含量的方法。考察了q NMR实验条件对测定结果的影响，选择六甲基磷酰三胺为内标、20%重水溶液（V/V）为溶剂，选择zgig脉冲序列、延迟时间30 s、扫描次数64次为实验条件，进行采样测试获取31P-q NMR谱，其中，六甲基磷酰三胺、α-甘油磷酸钠、β-甘油磷酸钠和磷酸的定量共振峰分别为δ 29.80、δ 0.69、δ 0.17和δ 0.03（供试品溶液p H≈4.8）。结果表明，31P-q NMR法测定α-甘油磷酸钠、β-甘油磷酸钠和磷酸的检出限分别为23.58、23.58和11.61μg/m L，定量限分别为78.60、78.60和38.70μg/m L，线性相关系数（R）均大于0.999，精密度小于0.6%，平均回收率为99.8%～103.2%，相对标准偏差（RSD）为0.41%～1.98%。本研究建立的31P-q NMR方法测定结果准确，稳定可靠。采用本方法测定了7批次不同厂家的浓维磷糖浆样品，其中，总磷量检测结果与比色法一致；甘油磷酸钠含量（α型与β型之和）偏低，约为标示量的82%；磷酸含量偏高。本方法操作简单、专属性强，适合作为浓维磷糖浆质量控制的方法。

关键词：定量核磁共振磷谱法浓维磷糖浆甘油磷酸钠磷酸

来源：博看期刊

Finite-temperature ductility-brittleness and electronic structures of Al_nSc（n=1,2 and 3）

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Rare Metals 2024年第8期43卷 3974-3989页

作者： Xue-Qian Wang Ying Zhao Hao-Xuan Liu Shu-Chen Sun Hong-Bo Yang Jia-Min Zhong Gan-Feng tu Song Li Yu-Dong Zhang Claude Esling Hai-Le Yan liang Zuo Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) School of Material Science and EngineeringNortheastern University School of Metallurgy Northeastern University Rare Earth Functional Materials (Xiong'an) Innovation Center Co. Ltd. Laboratoire d'étude des Microstructures et de Mécanique des Matériaux (LEM3) Unikersité de Lorraine

Finite-temperature ductility-brittleness and electronic structures of Al3Sc,Al2Sc and AlSc are studied comparatively by first-principles calculations and ab initio molecular *** show that Al3Sc and Al2Sc are brittle at both ground state and finite temperatures,while AlSc possesses a significantly superior *** ground state,AlSc is ductile from Pugh's and Poisson's criteria,while it is brittle in Pettifor's *** ductility of all Al3Sc,Al2Sc and AISc improves greatly with the elevated ***,the Cauchy pressure of AlSc undergoes a transition from negative to *** T> 600 K,AlSc is unequivocally classified as ductile from all criteria *** all compounds,the Al-Al bond originated from s-p and p-p orbital hybridizations,and the Al-Sc bond dominated by p-d covalent hybridization,are the first and second strongest chemical bonds,*** explain the difference in mechanical properties,the mean bond strength（MBS） is introduced in this *** weaker Al-Al bond in AlSc,leading to a smaller MBS,could be the origin of the softer elastic stiffness and superior intrinsic *** longer length of the Al-Al bond in AlSc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional *** longer length of the Al-Al bond in AISc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional ductility.

关键词： Al–Sc Target materials Intrinsic ductility Finite-temperature elastic constant First-principles calculation

Deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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tungsten 2024年第3期6卷 647-656页

作者： Cong Li Xiao-Wa Wang Ran-Ran Su Xuan-Xin Hu Shu-Guang Wei Han-Jun tu Li-Qun Shi Hong-liang Zhang Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern Physics Fudan University School of Mechanical Engineering Shanghai Jiao Tong University Department of Materials Science and Engineering University of Wisconsin

tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(D) *** study explores the blistering behavior and D supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C) ions with multiple energies and angles were *** samples were further irradiated with low-energy D ions under two fluences at temperatures from ～380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent D supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the D supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical D concentration for blistering,while a greater depth of damage facilitated the inward diffusion of D,thereby reducing the D concentration gradient and alleviating surface blistering.

关键词： tungsten Deuterium Supersaturated layer Blister Ion irradiation Pre-damage

Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)

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Horticultural Plant Journal 2024年第1期10卷 15-24页

作者： Qian Wang Dong Huang Wenyan tu Fengwang Ma Changhai Liu State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains *** this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple ***,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with *** Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related *** overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected *** results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes *** jointly contributed to GLS resistance in apple.

关键词： Apple MdIAA24 Glomerella leaf spot(GLS) Antioxidant capacity Auxin Salicylic acid Jasmonic acid

REEs recovery from molten salt electrolytic slag:Challenges and opportunities for environmentally friendly techniques

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Journal of Rare Earths 2024年第6期42卷 1009-1019,I0001页

作者： Ziyan Yang Faxin Xiao Shuchen Sun Heng Zhong Ganfeng tu School of Metallurgy Northeastern UniversityShenyang110819China Key Laboratory for Recycling of Nonferrous Metal Resources(Shenyang) Shenyang110819China

Due to the unique physical and chemical properties,rare earth elements(REEs)play a significant role in the high-tech *** the past few decades,the rare earth reserve in China has been gradually decreasing and more pressure has been exerted on the global rare earth supply for the increasing demand of REEs,which indicates that it is essential to recycle secondary resources to meet the rare earth *** for rare earth molten salt electrolytic slag(REMES),although its high rare earth content has potential huge economic value,its high fluorine content of approximately 10 wt%-20 wt%can pollute the *** methods are used to treat *** metallurgical and pyro-hydrometallurgical methods have gotten a big success for solving most of the hydrometallurgical problems,while some problems,like long route and waste water,need to be *** distillation is a new and promising method with a short process due to its harmlessness and high efficiency,but has shortcomings such as high energy consumption and material *** review presents these above three treatment methods,and the challenges and chances of using the recovery technique of REMES in an environmentally friendly way.

关键词： Rare earths Molten salt electrolytic slag Hydrometallurgy Pyro-hydrometallurgy Vacuum distillation Recovery

Insulation Design Rule for a Spacer in SF_(6)/N_(2)-filled DC Gas Insulated Apparatus

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 727-735页

作者： Hongyang Zhou Guoming Ma Meng Zhang Cong Wang Youping tu Chengrong Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China

A recurring challenge of a DC SF_(6)/N_(2)-filled GIS/GIL apparatus is the charge accumulation at DC *** conventional design rules and knowledge of AC spacers may not be applicable for this new type of apparatus.A novel design rule is proposed considering the effect of accumulated charge on the threshold of electric field strength being resistant to the superposed voltage.A surface charge accumulation simulation model is introduced,and the key parameters in the simulation model are *** addition,an experimental platform for a 100 kV spacer flashover test is *** flashover tests under superimposed voltage with opposing polarities are carried out,and the withstanding voltage of the spacer is ***,based on the proposed model,the threshold of the surface electric field strength(tangential component)on the DC spacer in SF_(6)/N_(2) mixed gases is *** a reliable insulation design of a DC GIS/GIL apparatus filled with 0.7 MPa SF_(6)/N_(2),the threshold of surface electric field strength on the DC spacer is 12 kV/*** insulation design rule can be referenced in the design of a high-voltage DC SF_(6)/N_(2)-filled GIS/GIL apparatus.

关键词： Charge accumulation DC spacer flashover voltage SF_(6)/N_(2) threshold of surface electric field strength

Quantifying the natural growth rate of hepatocellular carcinoma:A real-world retrospective study in southwestern China

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World Journal of Hepatology 2024年第5期16卷 800-808页

作者： Li tu Hong Xie Qi Li ping-Gui Lei Pei-Ling Zhao Fan Yang Chi Gong Yuan-Lin Yao Shi Zhou Department of General Practice The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004Guizhou ProvinceChina Clinical Medicine Soochow UniversitySuzhou 215123Jiangsu ProvinceChina Department of Radiology The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004Guizhou ProvinceChina Department of Clinical Laboratory Center The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004Guizhou ProvinceChina Key Laboratory of Biology and Medical Engineering Guizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina Department of Radiology Yanhe Tujia Autonomous County People's HospitalTongren 565300Guizhou ProvinceChina Department of Radiology The Qiandongnan Miao and Dong Autonomous Prefecture People's HospitalKaili 556000Guizhou ProvinceChina Department of Interventional Radiology The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004Guizhou ProvinceChina

BACKGROUND In recent years,approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma(HCC)have been reported in *** the high incidence of HCC,there remains a paucity of data regarding the natural growth pattern and the determination of optimal surveillance intervals specific to the Chinese *** To quantify the natural tumor growth pattern of HCC in regional *** A retrospective analysis was performed on patients from a single institution in Southwest China who had undergone two or more serial dynamic computed tomography or magnetic resonance imaging scans between 2014 and 2020,without having received any anti-cancer *** growth was assessed using tumor volume doubling time(TVDT)and tumor growth rate(TGR),with volumes measured manually by experienced *** univariate linear regression and descriptive analysis were applied to explore associations between growth rates and clinical *** This study identifies the median TVDT for HCC as 163.4 d,interquartile range(IQR)72.1 to 302.3 d,with a daily TGR of 0.42%(IQR 0.206%-0.97%).HCC growth patterns reveal that about one-third of tumors grow indolently with TVDT exceeding 270 d,another one-third of tumors exhibit rapid growth with TVDT under 90 d,and the remaining tumors show intermediate growth rates,with TVDT ranging between 3 to 9 *** The identified TGRs support biannual surveillance and follow-up for HCC patients in certain regions of *** the observed heterogeneity in HCC growth,further investigation is warranted.

关键词： Hepatocellular carcinoma Natural tumor growth pattern tumor volume doubling time tumor growth rate Realworld retrospective study

Influence of temperature, stress, and grain size on behavior of nano-polycrystalline niobium

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Chinese Physics B 2024年第7期33卷 467-474页

作者：晏玉平张柳亭张丽攀芦刚涂志新 School of Acronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang 330063China

Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS) on creep properties and mechanisms are investigated. Notably, the occurrence of tertiary creep is exclusively observed under conditions where the applied stress exceeds 4.5 GPa and the temperature is higher than 1100 K. This phenomenon can be attributed to the significant acceleration of grain boundary and lattice diffusion, driven by the elevated temperature and stress levels. It is found that the strain rate increases with both temperature and stress increasing. However, an interesting trend is observed in which the strain rate decreases as the grain size increases. The stress and temperature are crucial parameters governing the creep behavior. As these factors intensify, the creep mechanism undergoes a sequential transformation: initially from lattice diffusion under low stress and temperature conditions to a mixed mode combining grain boundaries(GBs) and lattice diffusion at moderate stress and mid temperature levels, and ultimately leading to the failure of power-law controlled creep behavior, inclusive of grain boundary recrystallization under high stress and temperature conditions. This comprehensive analysis provides in more detail an understanding of the intricate creep behavior of nano-polycrystalline niobium and its dependence on various physical parameters.

关键词： creep behavior molecular dynamics simulation activation energy stress exponent nano-polycrystalline niobium

Multi-scale collaborative design method for macroscopic thermal optimization and mesoscopic woven structure of hypersonic vehicle's TOCMC leading edge

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Chinese Journal of Aeronautics 2024年第4期37卷 524-541页

作者： Chenwei ZHAO Zecan tu Junkui MAO Jian HUI pingting CHEN College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 21016China Integrated Energy Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A new thermal protection design method for hypersonic vehicle's leading edge is proposed, which can effectively reduce temperature of the leading edge without additional cooling measures. This method reduces the leading-edge's temperature by the multi-scale collaborative design of the macroscopic thermal optimization and the mesoscopic woven structures of Three-dimensional Orthogonal Woven Ceramic Matrix Composites(TOCMC). The macroscopic thermal optimization is achieved by designing different mesoscopic woven structures in different regions to create combined heat transfer channels to dredge the heat. The combined heat transfer channel is macroscopically represented by the anisotropic thermal conductivity of TOCMC. The thermal optimization multiple linear regression model is established to optimize the heat transport channel, which predicts Theoretical Optimal Thermal Conductivity Configuration(TOTCC) in different regions to achieve the lowest leading-edge temperature. The function-oriented mesostructure design method is invented to design the corresponding mesostructure of TOCMC according to the TOTCC, which consists of universal thermal conductivity prediction formulas for TOCMC. These universal formulas are firstly derived based on the thermal resistance network method, which is verified by experiments with an error of 6.25%. The results show that the collaborative design method can effectively reduce the leading edge temperature by about 12.8% without adding cooling measures.

关键词： Multi-scale collaborative design Thermal optimization Ceramic matrix composite Hypersonic vehicle Thermal protection Intelligent optimization