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盐湖卤水中硼酸盐化学形态及Raman光谱定量分析

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光谱学与光谱分析 2024年第9期44卷 2514-2522页

作者：彭姣玉杨克利董亚萍冯海涛张波李武中国科学院青海盐湖研究所中国科学院盐湖资源综合高效利用重点实验室青海西宁810008 青海盐湖资源综合利用技术研究开发中心青海西宁810008 青海省盐湖资源化学重点实验室青海西宁810008

我国青藏盐湖以富含硼锂而著称,卤水中硼化学赋存状态随湖水化学类型的不同而发生变化,其中以硫酸盐型盐湖卤水中硼酸盐的存在形式变化最为复杂,卤水蒸发过程一般不以固体盐形式结晶析出,而是以多硼物种形式富集于氯化镁饱和老卤中,表... 详细信息

我国青藏盐湖以富含硼锂而著称,卤水中硼化学赋存状态随湖水化学类型的不同而发生变化,其中以硫酸盐型盐湖卤水中硼酸盐的存在形式变化最为复杂,卤水蒸发过程一般不以固体盐形式结晶析出,而是以多硼物种形式富集于氯化镁饱和老卤中,表现出严重的过饱和性,对后续锂盐和镁盐的分离提取影响较大。开展盐湖卤水体系中硼酸盐化学形态、分布规律及离子间作用机制等溶液化学研究对盐湖资源高效开发具有重要的意义。相比常规拉曼光谱技术,拉曼积分球基于拉曼散射原理可极大地提高激发光的使用效率和拉曼散射信号,对硼酸盐溶液结构检测具有拉曼响应信号强、检出限低、信噪比高等优点,为盐卤复杂体系硼酸盐化学形态的定量分析奠定了基础。利用拉曼积分球开展了盐湖卤水硼酸盐化学形态研究,阐述了卤水蒸发过程多硼酸根离子的变化规律;同时借助响应曲面法进行实验设计与优化,建立了共存盐类干扰回归模型用于盐湖卤水中单硼物种B(OH)_(3)的准确测定。结果表明,盐湖卤水浓缩过程中硼不断聚合生成多聚度硼酸根离子如B_(3)O_(3)(OH)_(4)^(-)和B_(6)O_(7)(OH)_(7)^(2-)等,硼的化学形态变化规律与碱土金属如MgCl_(2)-MgO-2B_(2)O_(3)-H_(2)O体系中硼物种变化一致,但与碱金属溶液体系物种变化差别较大。回归模型对卤水中正硼酸B(OH)_(3)定量分析的相对误差小于5%,准确度较高;阐明了蒸发浓缩过程中B(OH)_(3)物种分布的变化规律,从定量视角初步阐述了卤水富集过程硼酸根离子间的聚合作用关系,可为后续开展盐卤体系多硼物种分布及作用机制研究提供新思路、新方法。

关键词：卤水硼酸盐:响应曲面拉曼光谱定量分析

多站融合中考虑可靠性及经济性的储能站两阶段优化配置方法

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电力建设 2024年第7期45卷 134-143页

作者：王彦峰王春玲潘柏崇车伟娴许成昊董萍广东电网有限责任公司电网规划研究中心广州市510080 华南理工大学电力学院广州市510640

为研究储能站在多站融合中的多功能优化配置方法,首先探讨用储能站替代传统柴油发电机和不间断电源(uninterruptible power supply,UPS)的可能性,通过可靠度计算对传统模式及储能站模式进行对比,结果表明用储能站替代的可靠度更高。进... 详细信息

为研究储能站在多站融合中的多功能优化配置方法,首先探讨用储能站替代传统柴油发电机和不间断电源(uninterruptible power supply,UPS)的可能性,通过可靠度计算对传统模式及储能站模式进行对比,结果表明用储能站替代的可靠度更高。进而对储能站的经济性进行分析,建立储能寿命模型并进行成本分析,通过对比储能站的投资成本、运行维护成本以及度电成本确定储能类型。最后综合考虑多站融合中储能站的可靠性以及经济性,以储能站的可靠性最佳和年净收益值最大为目标函数配置储能容量,采用粒子群优化(particle swarm optimization PSO)算法得到储能的最佳配置容量为可用容量3500 kWh,备用容量150 kWh,所提出的两阶段优化方法使得多站融合中储能的配置容量更加精确并且贴合实际。

关键词：多站融合储能站数据中心可靠性评估经济性分析粒子群优化(PSO)

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化妆品质量安全负责人有关问题探讨

中国食品药品监管 2024年第2期 78-83页

作者：庞雪董江萍何淼沈阳药科大学工商管理学院中国健康传媒集团中国食品药品国际交流中心国家药品监督管理局

2021年1月1日起施行的《化妆品监督管理条例》首次确立了注册人备案人制度、质量安全负责人制度、功效宣称管理制度、风险监测和评价制度等一系列新制度。其中,质量安全负责人制度是压实企业主体责任的有效举措之一。《化妆品生产经营... 详细信息

2021年1月1日起施行的《化妆品监督管理条例》首次确立了注册人备案人制度、质量安全负责人制度、功效宣称管理制度、风险监测和评价制度等一系列新制度。其中,质量安全负责人制度是压实企业主体责任的有效举措之一。《化妆品生产经营监督管理办法》《化妆品生产质量管理规范》《企业落实化妆品质量安全主体责任监督管理规定》等对质量安全负责人的岗位及职责作出了细化规定,明确其是落实质量安全责任制的“关键岗位”和“关键人员”,对保障产品全生命周期质量安全意义重大。但笔者在实际工作接触中发现,很多化妆品企业尚未完全理解法规对质量安全负责人的要求,对其重视程度仍不够。本文从法规切入,详细阐述质量安全负责人的法定职责、履职条件、兼职及授权委托情形等,分析目前质量安全负责人在履职中存在的问题,给出解决建议,供行业参考。

关键词：化妆品质量安全负责人法规政策履职条件

A Novel Micro-hole Electrode Used to Investigate Electron Transfer Reactions at ITIES

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Chinese Chemical Letters 2002年第3期13卷 273-276页

作者： dong ping ZHAN Bing Liang WU Department of Chemistry Wuhan UniversityWuhan430072

A novel micro-hole electrode was fabricated to investigate the electron transfer reaction at the interface between two immiscible electrolyte solutions (ITIES). The electron transfer reaction between ferro/ferricyanide in aqueous phase (W) and ferrocene in 1, 2-dichloroethane (O) phase was studied as a test experiment. The results showed that the diffusion coefficient obtained from the micro-hole electrode was consistent with that obtained at macro-interface. Due to its simplicity and the very small IR drop it will be a useful tool for the study of ITIES systems.

关键词： Micro-hole electrode electron transfer ITIES.

Improved Ligand-Field Theoretical Calculations of R-Line Thermal Broadenings of MgO:Cr^(3+) and MgO:V^(2+)

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Communications in Theoretical Physics 2008年第11期50卷 1245-1248页

作者： ZHANG Zheng-Jie MA dong-ping Department of Physics Chengdu University of Technology Chengdu 610059 China Department of Applied Physics Sichuan University Chengdu 610065 China

With the values of parameters obtained from improved ligand-field theory,by taking into account all theirreducible representations and their components in EPI as well as all the levels and the admixtures of basic wavefunc-tions within d^3 electronic configuration,the R-line thermal broadenings(TB)of both MgO:Cr^(3+)and MgO:V^(2+)havemicroscopic-theoretically been *** results are in very good agreement with the experimental *** is foundthat the R-line TB of MgO:Cr^(3+)or MgO:V^(2+)comes from the first-order term of *** elastic Raman scattering ofacoustic phonons plays a dominant role in R-line TB of MgO:Cr^(3+)or MgO:V^(2+).

关键词： improved ligand-field theory electron-phonon interaction R line thermal broadening elastic Raman scattering

Staggered Quadrupolar Phase and Bicritical Point of Spin-1 Bond and Anisotropy Dilution Blume-Emery-Griffiths Model

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Communications in Theoretical Physics 2008年第2期49卷 511-515页

作者： dong Heng-ping YAN Shi-Lei Department of Physics Suzhou University Suzhou 215006 China Jiangsu Key Loboratory of Thin Films Suzhou University Suzhou 215006 China Department of Physics Nanjing University Nanjing 210093 China CCAST （World Loboratory） P.O. Box 8730 Beijing 100080 China

Within the effective field theory （EFT）, staggered quadrupolar phase and bicritical point of spin-1 bond and anisotropy dilution Blume-Emery-Griffiths model is studied on simple cubic lattice in the restricted range of biquadratic interaction and bilinear interaction ratio α≤-1. The phase diagrams present a line of staggered quadrupolarparamagnetic （SQ-P） phase and a line of ferromagnetic-paramagnetic （F-P） phase, separated by a bicritical point （BCP）. A large negative ratio and two different dilution factors magnify the range of the SQ phase and reduce range of ferro- magnetic phase in T-α or T-D plane. These parameters can assist the reentrant behavior of the SQ-P line and suppress that of the F-P line. The influence of bond dilution on the BCP is dissimilar to that of anisotropy dilution. There is a degenerate pattern at ground state in T-D plane. Some results obtained by the pure BEG model is in qualitative agreement with the results of Monte Carlo simulations.

关键词： Blume-Emery-Grifiiths model staggered quadrupolar phase bicritical point bond and anisotropy dilution

New Bivalved Arthropods from the Cambrian(Series 3, Drumian Stage) of Western Hunan, South China

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1388-1396页

作者： ZHANG Huaqiao dong Xi-ping XIAO Shuhai Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences School of Earth and Space Sciences Peking University Department of Geosciences Virginia TechBlacksburgVA 24061USA

We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian （Series 3, Drumian Stage） at Wangcun, Yongshun County, western Hunan, South China. They are bivalved arthropods, with thin, pliable, originally chitinous or chitin-calcareous shields （c. 350-517 I1 m long）. The shields are equipped with a pair of antero-dorsal spines. The spines are internally hollow, varying in length from 1/2 of to as long as the shield length in C. reticulata, and uniformly longer than the shield length in C. glabra. The spines of C. reticulata are ornamented with a longitudinal row of conical or blade-shaped denticles along the posterior edge. Cambrolongispina lacks marginal rims, valve lobation and sulci which are diagnostic of the Bradoriida sensu stricto. It also lacks a donblure/duplicature characteristic of phosphatocopids and some bradoriids. It could be related to the Monasteriidae （which may belong to Bradoriida sensu lato）, both characterized by a pair of antero-dorsal spines. Cambrolongispina may have been meiofaunai detritus feeders that lived on or within sediments. The antero-dorsal spines may have been sensory organs to detect nearby predators. The posterior denticles on these spines might have facilitated the sensory function of the spines.

关键词： bivalved arthropods Cambrian Wangcun western Hunan South China

心力衰竭患者血清25-羟维生素D水平特征分析

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中国实用乡村医生杂志 2024年第1期31卷 68-70,73页

作者：杜彦梅衣欣董平北京市回民医院心血管内科北京100054

目的探讨心力衰竭患者血清25-羟维生素D水平特征。方法选取2018年6月—2023年3月在北京市回民医院心血管内科进行治疗的198例心力衰竭患者作为心衰组,选择同期在我院进行健康体检的200名健康体检者作为健康组。比较心衰组和健康组一... 详细信息

目的探讨心力衰竭患者血清25-羟维生素D水平特征。方法选取2018年6月—2023年3月在北京市回民医院心血管内科进行治疗的198例心力衰竭患者作为心衰组,选择同期在我院进行健康体检的200名健康体检者作为健康组。比较心衰组和健康组一般资料情况及血清25-羟维生素D水平。比较心衰组不同心功能分级人群血清25-羟维生素D水平,以及心衰组不同血清25-羟维生素D水平人群出院后随访6个月内心血管不良事件发生情况。结果心衰组与健康组一般资料差异无统计学意义(P>0.05)。心衰组患者血清25-羟维生素D水平低于健康组,差异有统计学意义(P<0.05)。心衰组患者随着心功能分级的升高即心功能下降,血清25-羟维生素D水平降低,差异有统计学意义(P<0.05)。心衰组患者出院后6个月内,随着患者血清25-羟维生素D水平的降低,心血管不良事件发生率增高,差异有统计学意义(P<0.05)。结论心力衰竭患者血清25-羟维生素D水平低于健康者,且随着患者病情的加重其心功能降低,血清25-羟维生素D水平呈下降趋势,心血管不良事件发生率呈上升趋势。因此,临床对于心力衰竭患者应评估其血清25-羟维生素D水平,对于25-羟维生素D不足者应及时给予补充干预,以降低心血管不良事件的发生风险,提升患者预后。

关键词：心力衰竭血清25-羟维生素D水平心功能心血管不良事件

Crystallization,Mechanical,Thermal and Rheological Properties of Polypropylene Composites Reinforced by Magnesium Oxysulfate Whisker

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Chinese Journal of Polymer Science 2017年第5期35卷 659-671页

作者： Li Dang Xue-ying Nai Xin Liu dong-hai Zhu Ya-ping dong 李武 Key Laboratory of Salt Lake Resources Chemistry Qinghai Institute of Salt LakesChinese Academy of Sciences Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences University of Chinese Academy of Sciences

Polypropylene （PP） composites containing magnesium oxysulfate whisker （MOSw） or lauric acid （LA） modified MOSw （LAMOSw） were prepared via melt mixing in a torque rheometer. The heterogeneous nucleating effect of LAMOSw was clearly observed in polarized light microscopy （PLM） pictures with the presence of an abundance of small spherulites. MOSw exhibited no nucleation effect and formed a few spherulites with large size. Compared with PP/MOSw composites, PP/LAMOSw exhibited better impact strength, tensile strength and nominal strain at break, ascribing to three possible reasons：（i） more β-crystal PP formed, （ii） better dispersity of LAMOSw in PP matrix and （iii） the plasticizing effect of LA. The results of dynamic mechanical thermal analysis （DMTA） indicated that brittleness of the PP matrix at low temperature was improved by the addition of LAMOSw, while the interracial interactions between MOSw and PP matrix were actually weakened by LA, as evidenced by the higher tan8 values over the entire range of test temperatures. In terms of the rheological properties of the composites, both the η＊ and G＇ at low frequencies increase with the addition of MOSw or LAMOSw, indicating that the PP matrix was transformed from liquid-like to solid-like. However, a network of whiskers did not form because no plateau was found in the G＇ at low frequencies. With low filler content, LAMOSw produced a stronger solid-like behavior than MOSw mainly due to the better dispersion of the LAMOSw in PP matrix. However, for highly-filled composites, the η＊ of PP/LAMOSw at low frequencies was smaller than that of PP/MOSw composite, since the particle- particle contact effect played a major role.

关键词： PP/MOSw composites Crystallization Thermal properties Mechanical properties Rheological properties