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Recovery of gold from refractory gold ores: Effect of pyrite on the stability of the thiourea leaching system

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 956-964页

作者： hong Qin Xue-yi guo Qing-hua Tian Lei Zhang School of Metallurgy and Environment Central South UniversityChangsha 410083China National&Regional Joint Engineering Research Center of Nonferrous Metal Resource Recycling Changsha 410083China

The extraction of gold from refractory gold ores(RGOs)without side reactions is an extremely promising ***,most RGOs contain large amounts of sulfide,such as ***,investigation of the influence of sulfide on the gold leaching process is important to maximize the utilization of *** this work,the effects of pyrite on the stability of the thiourea system were systematically investigated under different *** showed that the decomposition rate of thiourea was accelerated sharply in the presence of *** effect of pyrite on gold recovery in thiourea leaching systems was then confirmed via a series of *** decomposition efficiency of thiourea decreased by 40%and the recovery efficiency of gold increased by 56%after the removal of sulfide by *** optimal conditions,the efficiency of the gold recovery system increased to 83.69%and only 57.92%of thiourea decomposition was *** high consumption of thiourea by the leaching system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in the ores,such as pyrite and soluble ferric oxide.

关键词： thiourea leaching stability pyrite refractory gold ores

Carbon dots embedded nanofiber films:Large-scale fabrication and enhanced mechanical properties

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Chinese Chemical Letters 2022年第1期33卷 304-307页

作者： Chang Liu Rui Cheng Jiazhuang guo Ge Li He Li hong-Gang Ye Zhi-Bin liang Cai-Feng Wang Su Chen State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineeringand Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer MaterialsNanjing Tech UniversityNanjing 210009China

Valuable application prospects and large-scale production technologies are powerful driving forces for the development of materials *** dots(CDs)are a kind of promising carbon-based fluorescent nanomaterials,which possess wide application prospects based and even beyond the fluorescence ***,we report the fast and high-yield synthesis of CDs and the large-scale preparation of fluorescent nanofiber films with enhanced mechanical *** were prepared from magnetic hyperthermia treatment of citric acid and carbamide,with the output of 25.37 g in a single *** asprepared CDs exhibit a high absolute photoluminescence(PL)quantum yield(QY)of 67%and wonderful dispersibility in polar ***,solution blow spinning of CDs and polymer matrixes of alcohol soluble polyurethane(APU)and polyacrylonitrile(PAN)led to large-area fluorescent CDs-embedded nanofiber films,APU/CDs(size:120 cm×18 cm)and PAN/CDs(size:120 cm×22 cm),*** resultant large-area APU/CDs and PAN/CDs nanofiber films have dramatically enhanced mechanical properties,to show integrated improvement of tensile strength and elongation.

关键词： Carbon dots Mass production Solution blow spinning Nanofiber Mechanical properties

Effects of returns on composition,microstructure and mechanical properties of GH4169 superalloy

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China Foundry 2017年第4期14卷 244-250页

作者： Yong-liang Pu Sheng-zhong Kou Zhi-dong Zhang Tian-wen Dong Xiao-fan guo hong-xia Qu State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou Universityof TechnologLanzhou 730050China Key Laboratory of Non-ferrous Metal Alloys and Processing of the Ministry of Education Lanzhou University of TechnologyLanzhou 730050China

To recycle the returned alloy effectively, effects of returns proportion on alloy composition, microstructure and compression properties of superalloy GH4169 were studied by means of scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and thermal-mechanical simulator. The results show that returns addition has no significant effect on the main alloy elements content and the principle precipitates, but increases the volume fraction of Al_2O_3 inclusions, resulting in the increase of oxygen level of GH4169 alloy. Returns addition does not change the elastic and plastic deformation process at room temperature or at 1,150 °C, but high returns proportion GH4169 alloy shows improved compression strength and yield strength. The alloy with 100% returns shows a maximum compression strength 1,153.45 MPa at room temperature, while the alloy with 80% returns has a maximum value 69.3 MPa at 1,150 °C. Returns addition increases fluctuation range and reduces the stability of yield strength and compression strength of GH4169 alloy at room temperature. It is noted that the volume fraction and the size of Al_2O_3, and the fraction of Laves phase reach their maximum values in the GH4169 alloy with 60% returns, which exhibits maximum yield strength of 516.65 MPa at room temperature and 62.17 MPa at 1,150 °C.

关键词： superalloy returns proportion composition microstructure mechanical properties

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“地步”负面立场标记的嬗变

辽东学院学报（社会科学版） 2024年第1期26卷 64-70页

作者：曹建清李国宏西华大学外国语学院四川成都610039

受汉语双音化趋势影响,“地步”双音化后进而词汇化,最终演变为表达说话者情感和态度的负面立场标记。其主观化路径为物理距离→心理距离→程度义,这一过程伴随着言者主观性的不断强化,体现了语义演变与主观化的互动。“地步”表达“心... 详细信息

受汉语双音化趋势影响,“地步”双音化后进而词汇化,最终演变为表达说话者情感和态度的负面立场标记。其主观化路径为物理距离→心理距离→程度义,这一过程伴随着言者主观性的不断强化,体现了语义演变与主观化的互动。“地步”表达“心理距离”时,其语义的主观性开始显现;表达程度义时,主观性进一步增强;最终,当“地步”作为负面立场标记使用时,主观性达到顶峰。语言内部,语素“地”的贬义色彩以及“地步”共现成分的负面义,均为“地步”负面立场标记的形成提供了有力条件。语言外部,主观化、语用推理以及语用因素的共同作用,则进一步诱发了“地步”负面立场标记的产生。

关键词：主观化语用推理语义演变负面立场标记

Application of a new basalt fiber-reinforced polymer anchorage structure in the tunnel–slope system under rainfall action

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Journal of Mountain Science 2023年第2期20卷 570-584页

作者： TANG Lin WU hong-gang WEI hong FENG Kang RENG guo-jun College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China China Northwest Research Institute Co.Ltd.of CREC Lanzhou 730070China College of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621000China

The application of basalt fiber-reinforced polymer(BFRP)anchors has gained significant attention,particularly in the field of geotechnical anchorage engineering because of its high strength and corrosion *** research on the applicability of BFRP anchor in a tunnel–slope system under rainfall is of practical significance to solve the problem of instability damage to anchored slopes caused by corrosion of steel *** this study,model tests of BFRP and steel anchorage structures were conducted to compare their reinforcement capability in a tunnel–slope system under heavy *** results show that the BFRP anchorage structure is better than the steel in coordinating slope deformation and stabilizing earth pressure around the *** deformation of slopes under rainfall is classified into four stages:initial,isokinetic,accelerated,and blocked *** anchors have the same axial strain distribution pattern as the steel anchors,and they are convexly distributed along the axial direction of the *** correlation analysis and Pearson linear correlation analysis of the multi-attribute data of the slope and BFRP anchors showed a positive correlation among BFRP anchor strain,earth pressure inside the slope,slope deformation displacement,and accumulated *** research results provide a basis and reference for the application of BFRP anchors in the anchorage engineering of the tunnel–slope system under rainfall action.

关键词： BFRP anchors Steel anchors Rainfall Tunnel-slope system

Time-dependent Density Functional-based Tight-bind Method Efficiently Implemented with OpenMP Parallel and GPU Acceleration

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Chinese Journal of Chemical Physics 2013年第6期26卷 635-645,I0003页

作者： guo-hong Fan Ke-li Han guo-zhong He State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 116023 China

The time-dependent density functional-based tight-bind （TD-DFTB） method is implemented on the multi-core and the graphical processing unit （GPU） system for excited state calcu-lations of large system with hundreds or thousands of atoms. Sparse matrix and OpenMP multithreaded are used for building the Hamiltonian matrix. The diagonal of the eigenvalue problem in the ground state is implemented on the GPUs with double precision. The GPU- based acceleration fully preserves all the properties, and a considerable total speedup of 8.73 can be achieved. A Krylov-space-based algorithm with the OpenMP parallel and CPU acceleration is used for finding the lowest eigenvalue and eigenvector of the large TDDFT matrix, which greatly reduces the iterations taken and the time spent on the excited states eigenvalue problem. The Krylov solver with the GPU acceleration of matrix-vector product can converge quickly to obtain the final result and a notable speed-up of 206 times can be observed for system size of 812 atoms. The calculations on serials of small and large systems show that the fast TD-DFTB code can obtain reasonable result with a much cheaper computational requirement compared with the first-principle results of CIS and full TDDFT calculation.

关键词： Density-functional theory Tight-binding method Time-dependent densityfunctional theory Excited state Graphical processing unit Krylov iterative algorithm Sparse matrix OpenMP

杞荷分清饮中12种成分在正常及糖尿病模型大鼠体内药动学的比较研究

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中国中药杂志 2024年第5期49卷 1378-1387页

作者：陈江燕郭盛许小雪杨雅朱悦康宏杰段金廒南京中医药大学中药资源产业化与方剂创新药物国家地方联合工程研究中心江苏省中药资源产业化过程协同创新中心国家中医药管理局中药资源循环利用重点研究室江苏南京210023 宁夏枸杞创新中心宁夏银川750002

研究杞荷分清饮中12种活性成分(琥珀酸、新绿原酸、绿原酸、隐绿原酸、原儿茶醛、咖啡酸、5-O-阿魏酰奎宁酸、对香豆酸、荷叶碱、槲皮素、齐墩果酸、熊果酸)在正常和糖尿病模型大鼠体内的药动学差异。采用高脂饲料喂养联合腹腔注射链脲... 详细信息

研究杞荷分清饮中12种活性成分(琥珀酸、新绿原酸、绿原酸、隐绿原酸、原儿茶醛、咖啡酸、5-O-阿魏酰奎宁酸、对香豆酸、荷叶碱、槲皮素、齐墩果酸、熊果酸)在正常和糖尿病模型大鼠体内的药动学差异。采用高脂饲料喂养联合腹腔注射链脲佐菌素建立糖尿病大鼠模型,建立超高效液相色谱-三重四极杆-线性离子阱质谱(UHPLC-QTRAP-MS/MS)方法,同时测定正常大鼠和模型大鼠分别单次灌胃给予杞荷分清饮后血浆中12种成分的含量。结果显示,所建立的分析方法对12种所测定成分线性关系良好,专属性、准确度、精密度、稳定性等方法学均符合要求。采用DAS 3.2.8软件拟合计算药动学参数结果表明,模型组中除咖啡酸、5-O-阿魏酰奎宁酸、齐墩果酸外其余9种成分半衰期时间(t1/2)相对正常组延长;隐绿原酸、对香豆酸、熊果酸、齐墩果酸药时曲线下面积(AUC0-t)模型组相对正常组增加,且平均驻留时间(MRT)延迟;正常组中槲皮素、荷叶碱出现“双峰”现象,模型组未见,提示疾病状态下药物的药动学参数出现明显差异。

关键词：杞荷分清饮枸杞叶糖尿病药代动力学

Quantification of eight components in Paeonia lactiflora and Glycyrrhiza decoction using UHPLC-MS/MS

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Journal of Chinese Pharmaceutical Sciences 2024年第9期33卷 837-845页

作者： Hao Jiang Yushu guo Chao Shi Department of Pharmacy Medical Supplies Center of PLA General HospitalBeijing 100048China

Hao Jiang;Yushu guo;Chao Shi;Department of Pharmacy,Medical Supplies Center of PLA General Hospital;This study aimed to utilize ultra-high-performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)to analyze and quantify eight therapeutic components in Paeonia lactiflora and Glycyrrhiza *** goal was to establish an accurate,efficient,and applicable method for determining the composition of this formula,providing a reference for its clinical *** was employed to extract the therapeutic components from Paeonia lactiflora and Glycyrrhiza decoction,forming the test sample ***-MS/MS technology was applied to separate and analyze the test *** results indicated that upon analysis,the eight reference standards exhibited excellent linear relationships,and the test samples remained stable within 24 *** content of paeoniflorin,paeonolide,glycyrrhizic acid A,quercetin,chebulic acid,liquiritin,naringenin,and glycyrrhetic acid was determined to be 3.530±0.124,0.139±0.006,0.245±0.008,0.779±0.026,0.433±0.021,0.388±0.018,0.617±0.013,and 0.081±0.005 mg/m L,*** study established that UHPLC-MS/MS analysis demonstrated high efficiency and broad applicability,reflecting the chemical composition characteristics of Paeonia lactiflora and Glycyrrhiza *** research provided a quantitative analysis method for the eight therapeutic components in Paeonia lactiflora and Glycyrrhiza decoction,applicable to its clinical use and quality control.

关键词： Paeonia lactiflora and Glycyrrhiza decoction UHPLC-MS/MS Medicinal composition Content determination

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绞股蓝中4个新达玛烷型三萜皂苷的分离鉴定

药学学报 2024年第8期59卷 2288-2294页

作者：杨光梁海珍张洁陈晓娟郭宝林马百平广东药科大学广东广州510006 军事科学院军事医学研究院辐射医学研究所北京100850 中国医学科学院、北京协和医学院药用植物研究所北京100193

本文对广西产绞股蓝[Gynostemma pentaphyllum (Thunb.) Makino]中达玛烷型三萜皂苷成分进行研究,综合使用D101大孔吸附树脂、硅胶和C18柱色谱以及制备型高效液相色谱等分离手段,从中分离得到4个达玛烷型三萜皂苷类化合物,利用MS、NMR... 详细信息

本文对广西产绞股蓝[Gynostemma pentaphyllum (Thunb.) Makino]中达玛烷型三萜皂苷成分进行研究,综合使用D101大孔吸附树脂、硅胶和C18柱色谱以及制备型高效液相色谱等分离手段,从中分离得到4个达玛烷型三萜皂苷类化合物,利用MS、NMR和圆二色谱(CD)等波谱技术鉴定其结构,分别为3β,12β-二羟基-25-过氧氢基达玛烷-20,23-二烯-3-O-[β-D-吡喃葡萄糖基(1→2)]-β-D-吡喃葡萄糖苷(1)、3β,12β,24S-三羟基达玛烷-20,25-二烯-3-O-[β-D-吡喃葡萄糖基(1→2)]-β-D-吡喃葡萄糖苷(2)、3β,20α-二羟基-24-烯-12β,22S-环氧达玛烷-3-O-[β-D-吡喃葡萄糖基(1→2)]-β-D-吡喃葡萄糖苷(3)、3β,12β,20S-三羟基达玛烷-24-烯-3-O-[6-O-乙酰基-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-β-D-吡喃木糖基(1→3)-α-L-吡喃鼠李糖基(1→6)-β-D-吡喃葡萄糖苷(4)。化合物1~4均为新化合物。

关键词：葫芦科绞股蓝三萜皂苷分离结构鉴定