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微细粒钛铁矿选矿技术研究进展 预览
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作者 张松 文书明 +3 位作者 刘建 先永骏 韩广 王瑜 《矿产保护与利用》 2019年第1期131-137,共7页
综述了微细粒钛铁矿浮选药剂的种类和机理、选别设备的特点以及微细粒级钛铁矿的选别工艺。结合实际案例,分析了调整剂和捕收剂的作用机理、介绍了新设备的研制和工艺流程的创新与运用。微细粒钛铁矿选矿技术研究的现状是研制具有协同... 综述了微细粒钛铁矿浮选药剂的种类和机理、选别设备的特点以及微细粒级钛铁矿的选别工艺。结合实际案例,分析了调整剂和捕收剂的作用机理、介绍了新设备的研制和工艺流程的创新与运用。微细粒钛铁矿选矿技术研究的现状是研制具有协同效应的组合药剂以及应用复合力场的新型设备。多数选钛厂采用磁选与浮选联合工艺选别微细粒钛铁矿。实际生产中微细粒钛铁矿的回收率低,-0.019mm粒级钛铁矿缺乏有效的选别方法是研究过程中面临的难点。 展开更多
关键词 微细粒 钛铁矿 浮选药剂 设备 选别工艺 作用机理
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Ectomycorrhizal and Saprotrophic Fungal Communities Vary Across mm-Scale Soil Microsites Differing in Phosphatase Activity
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作者 Aaron GODIN Denise BROOKS +1 位作者 Sue J. GRAYSTON Melanie D. JONES 《土壤圈:英文版》 SCIE CAS CSCD 2019年第3期344-359,共16页
To understand nutrient cycling in soils, soil processes and microorganisms need be better characterized. To determine whether specific trophic groups of fungi are associated with soil enzyme activity, we used soil imp... To understand nutrient cycling in soils, soil processes and microorganisms need be better characterized. To determine whether specific trophic groups of fungi are associated with soil enzyme activity, we used soil imprinting to guide mm-scale sampling from microsites with high and low phosphatase activities in birch/Douglas-fir stands. Study 1 involved sampling one root window per site at 12 sites of different ages(stands);study 2 was conducted at one of the stem-exclusion stands, at which 5 root windows had been installed. Total fungal and ectomycorrhizal(EM) fungal terminal-restriction fragment length polymorphism(TRFLP)fingerprints differed between high-and low-phosphatase activity microsites at 8 of 12 root windows across 12 sites. Where differences were detected, fewer EM fungi were detected in high-than low-phosphatase activity microsites. Using 5 root windows at one site,next-generation sequencing detected similar fungal communities across microsites, but the ratio of saprotrophic to EM fungal reads was higher in high-phosphatase activity microsites in the two windows that had low EM fungal richness. In windows with differences in fungal communities, both studies indicated that EM fungi were less successful than saprotrophic fungi in colonizing fine-scale,organic matter-rich microsites. Fine-scale sampling linked with in situ detection of enzyme activity revealed relationships between soil fungal communities and phosphatase activity that could not be observed at the scales employed by conventional approaches, thereby contributing to the understanding of fine-scale phosphorus cycling in forest soils. 展开更多
关键词 ectomycorrhizae fine SCALE FUNGAL communities PHOSPHATASE root windows saprotrophic fungi SOIL IMPRINTING
A Method for Calculating Bottom Backscattering Strength Using Omnidirectional Projector and Omnidirectional Hydrophone 预览
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作者 YU Kaiben YU Shengqi +4 位作者 LIU Baohua LIU Zhongchen YANG Zhiguo KAN Guangming ZONG Le 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期358-364,共7页
A method of obtaining bottom backscattering strength by employing an omnidirectional projector and omnidirectional hydrophone is proposed.The backscattering strength is extracted from monostatic backscattering data.Th... A method of obtaining bottom backscattering strength by employing an omnidirectional projector and omnidirectional hydrophone is proposed.The backscattering strength is extracted from monostatic backscattering data.The method was adopted in an experiment conducted in the South Yellow Sea of China.The seafloor surface was relatively smooth and covered by a small quantity of shell fragments,as observed through a digital camera system.Sampling data showed that the main component of the sediment at this experimental site was fine sand.In this paper,we detail the calculation method.Preliminary results of backscattering strength as a function of grazing angle(20°–70°)in the frequency range of 6–24 kHz are presented.The measured backscattering strength increased with the grazing angle and changed more rapidly at large grazing angles(60°–70°).A comparison of the data at different frequencies reveals that the measured backscattering strength substantially rises with the increase of acoustic frequency.A fitting curve of Lambert’s law against the measured data shows that the backscattering strength deviates from Lambert’s law at large grazing angles. 展开更多
关键词 acoustic scattering BOTTOM BACKSCATTERING STRENGTH fine sand Lambert’s law
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Tribo-charging of binary mixtures composed of coarse and fine particles in gas-solid pipe flow
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作者 Haifeng Wang Farzam Fotovat +1 位作者 Xiaotao T. Bi John R. Grace 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期101-109,共9页
Experiments were conducted to investigate the effect of adding fines on the tribo-charging of coarse glass beads. Four types of fines, i.e., copper, stainless steel, uncoated and silver-coated fine glass beads, mixed ... Experiments were conducted to investigate the effect of adding fines on the tribo-charging of coarse glass beads. Four types of fines, i.e., copper, stainless steel, uncoated and silver-coated fine glass beads, mixed w让h 240-830 μm glass beads were conveyed by air through a stainless-steel spiral pipe acting as a tribo-charger. Regardless of the type or electrical conductivity of the fine particles tested, adding small amounts of fines (up to 10wt%) to coarse glass beads resulted in a sharp increase in the mass and surface charge densities of the particles. In gen eral, the profiles of the mass and surface charge den sides of the fine-coarse particle mixtures as a function of the mixture composition were determined by the relative magnitude of contact potential differences and the total surface areas of all the comp on ents. The domi nant particle tri bo-electrification mecha nism switched from coarse particle-wall con tacts to fine particle-wall contacts when the fines weight percentage in the mixture exceeded 10%. A model was developed to predict the mass charge density of bi nary mixtures as a function of the mixture composition. 展开更多
关键词 Tribo-charging ELECTROSTATICS FINE particles BINARY MIXTURE GAS-SOLID flow
基于大数据的医疗成本监管路径分析 预览
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作者 惠华强 郑萍 +1 位作者 蒲凤萍 朱海荣 《中国卫生质量管理》 2019年第1期81-83,共3页
从加强医院成本精细化监管,加强医院成本数据化监管,加强医院成本标准化监管3方面,对医院医疗成本监管路径进行阐述,旨在利用数据挖掘、应用数据仓库等技术手段,建立一套统一、科学、系统的精细化管理模式,涵盖医疗成本全过程,提高医疗... 从加强医院成本精细化监管,加强医院成本数据化监管,加强医院成本标准化监管3方面,对医院医疗成本监管路径进行阐述,旨在利用数据挖掘、应用数据仓库等技术手段,建立一套统一、科学、系统的精细化管理模式,涵盖医疗成本全过程,提高医疗服务水平。 展开更多
关键词 医院 大数据 信息化 医疗成本管控 精细化
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A method to improve fluidization quality in gas-solid fluidized bed for fine coal beneficiation
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作者 Chenyang Zhou Xuchen Fan +1 位作者 Chenlong Duan Yuemin Zhao 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期181-192,共12页
Dry coal separation has become essential in China because it does not consume water and it reduces environmental pollution. In this study, a method for improving fluidization quality in a fluidized bed separator using... Dry coal separation has become essential in China because it does not consume water and it reduces environmental pollution. In this study, a method for improving fluidization quality in a fluidized bed separator using a micropore sponge is proposed. The separator is used for fine coal beneficiation. The pressure drop across the distributor and bed fluidization characteristics were analyzed to evaluate fluidization quality. The beneficiation efficiency for fine coal was further investigated by using a laboratory-scale fluidized bed with and without a micropore sponge. With the sponge, the highest pressure drop fluctuation factor decreased from 0.23 to 0.16, indicating an improvement in density stability. The modified separation method reduced the ash content of a sample of fine coal from 23.83% to 10.70%. The probable error efficiency value E for -6 + 3 mm coal was 0.12g/cm^3, close to the efficiency error values reported for other dry-beneficiation techniques. The separation results show that using a sponge in the fluidized bed can readily improve the efficiency of fine coal beneficiation. 展开更多
关键词 Fluidized bed COAL BENEFICIATION MICROPORE SPONGE Fine COAL Dry separation DISTRIBUTOR
2012-2017年河南省卫生行政处罚情况分析
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作者 贺容刚 《河南预防医学杂志》 2019年第4期258-263,共6页
目的分析2012-2017年河南省卫生行政处罚的整体情况及存在问题,为制定卫生监督政策和监督执法提供基础资料和理论依据。方法分析数据来源于国家卫生监督信息数据库,从其中导出河南省2012-2017年间所有行政处罚案件数据,共64 305件,建立... 目的分析2012-2017年河南省卫生行政处罚的整体情况及存在问题,为制定卫生监督政策和监督执法提供基础资料和理论依据。方法分析数据来源于国家卫生监督信息数据库,从其中导出河南省2012-2017年间所有行政处罚案件数据,共64 305件,建立数据库并进行统计分析。结果 6年中河南省共实施卫生行政处罚案件64 305件,警告33 932次,吊销许可证或科目共40个,罚款115 737 284.85元,案均值为2086.70元。近5年来案均值逐年上升,案件数量、罚款金额呈现先增加后降低趋势。个体私有及其它类别的行政管理相对人处罚案件最多,案均值较低,对行政处罚较敏感;国有全资相对人案件数量较少,案均值最高,对行政处罚不敏感。传染病违法案件逐年上升,已成为目前最主要的处罚案件来源,公共场所无证经营问题已经超过非法行医成为最主要的无证问题。结论河南省卫生行政处罚取得了明显效果,但是监督监测手段亟待增强,传染病违法问题和公共场所无证经营问题应当引起高度重视,案均值有待进一步提高。立法者和执法者应当着力于让相对人承担的行政责任与其违法收益相匹配,提高相对人的违法成本,切实增强相对人承担行政责任时的心痛效应,以便达到教育警示作用。 展开更多
关键词 行政处罚 卫生监督 行政责任 罚款 心痛效应
Fine Individual Selection of Camellia pitardii in Pengshui County 预览
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作者 Xiaomei TAN Rong ZHANG +2 位作者 Yunfeng GUAN Xiangshun DENG Ya WANG 《农业生物技术:英文版》 CAS 2019年第2期104-107,共4页
In order to select improved varieties, a study on the fine individual selection was carried out in Pengshui County, Chongqing Province. For 14 fine individuals with high and stable yield preliminarily screened, eight ... In order to select improved varieties, a study on the fine individual selection was carried out in Pengshui County, Chongqing Province. For 14 fine individuals with high and stable yield preliminarily screened, eight factors (fruit height, fruit diameter, pericarp thickness, fresh fruit weight, fresh seed weight, dry seed weight, dry seed yield and fresh seed yield) related to yield were selected to perform principal component analysis, and based on comprehensive scores and oil contents, five fine individuals (Longshe Town 7, 8, 12, 17 and Shaoqing Street 2) of Camellia pitardii were determined. These fine individuals have a better performance. 展开更多
关键词 CAMELLIA pitardii FINE individuals Principal COMPONENT ANALYSIS
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Surface molecular doping of all-inorganic perovskite using zethrenes molecules
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作者 Arramel Hu Pan +10 位作者 Aozhen Xie Songyan Hou Xinmao Yin Chi Sin Tang Nguyen T.Hoa Muhammad D.Birowosuto Hong Wang Cuong Dang Andrivo Rusydi Andrew T.S.Wee Jishan Wu 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第1期77-84,共8页
We present an optical and photoelectron spectroscopic study to elucidate the interfacial electronic properties of organic-inorganic semiconductor heterojunctions formed in a kinetically blocked heptazethrene triisopro... We present an optical and photoelectron spectroscopic study to elucidate the interfacial electronic properties of organic-inorganic semiconductor heterojunctions formed in a kinetically blocked heptazethrene triisopropylsilyl ethynylene (HZ-TIPS) and its homologue,octazethrene (OZ-TIPS) on an all-inorganic perovskite cesium lead bromide (CsPbBr3) surface.The photoluminescence behavior of the underlying perovskites upon differing molecular doping conditions was examined.It turns out that the charge transfer dynamics of thermally-evaporated OZ-TIPS molecule exhibited a faster average lifetime than that of the HZ-TIPS case suggesting the importance of the biradical state in the former molecule.An interfacial dipole was formed at the interface due to the competing interaction between the dispersion force of the bulky TIPS-substituent group and the attractive van der Waals interaction at the first few layers.Photoemission spectroscopy of the physisorbed HZ-TIPS shows chemical shifts,which indicates electron transfer from HZ-TIPS molecules to the CsPbBr3 perovskite single crystal.In contrast,the adsorbed OZ-TIPS molecular layer on CsPbBr3 demonstrates the opposite trend indicating a hole transfer process.The average molecular orientation as determined by near edge X-ray absorption fine structure (NEXAFS) suggests that the HZ-TIPS molecular plane is generally lifted with respect to the perovskite surface.We suggest that the nature of the closed-shell electronic ground state of HZ-TIPS could contribute to the formation of interfacial dipole at the molecule/perovskite interface. 展开更多
关键词 zethrene PHOTOELECTRON spectroscopy PEROVSKITE near edge X-ray absorption fine structure and MOLECULAR DOPING
博弈论视角下的碳交易价格对治理雾霾的影响 预览
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作者 杨昆 《科技创新导报》 2019年第8期244-247,共4页
在政府与企业间进行智猪博弈时,纳什均衡为政府主持碳交易时,企业参与碳交易;完全但不完美动态博弈条件下的政府与企业博弈时,最优纳什均衡是当罚金处于碳交易的高定价与低定价的均值附近时,企业才会参加碳交易;提出了碳交易时出现的问... 在政府与企业间进行智猪博弈时,纳什均衡为政府主持碳交易时,企业参与碳交易;完全但不完美动态博弈条件下的政府与企业博弈时,最优纳什均衡是当罚金处于碳交易的高定价与低定价的均值附近时,企业才会参加碳交易;提出了碳交易时出现的问题及解决问题的路径,包括罚金定额最优化的路径、解决政企冲突的路径、砸烂政企共同利益的路径、降低企业碳交易成本的路径、扩大企业的边际减排成本差距的路径。 展开更多
关键词 碳交易价格 智猪博弈 完全但不完美动态A博弈 罚金 雾霾
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Present state of endoscopic ultrasonography-guided fine needle aspiration for the diagnosis of autoimmune pancreatitis type 1 预览
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作者 Mitsuru Sugimoto Tadayuki Takagi +11 位作者 Rei Suzuki Naoki Konno Hiroyuki Asama Yuki Sato Hiroki Irie Ko Watanabe Jun Nakamura Hitomi Kikuchi Mika Takasumi Minami Hashimoto Takuto Hikichi Hiromasa Ohira 《世界荟萃分析杂志》 2019年第5期218-223,共6页
Autoimmune pancreatitis(AIP)is defined as pancreatitis caused by irregular narrowing of the pancreatic duct accompanied by pancreatic swelling,fibrosis and lymphocyte infiltration,events that are related to autoimmune... Autoimmune pancreatitis(AIP)is defined as pancreatitis caused by irregular narrowing of the pancreatic duct accompanied by pancreatic swelling,fibrosis and lymphocyte infiltration,events that are related to autoimmune mechanisms.The 2010 International Consensus Diagnostic Criteria for AIP defined pancreatitis as“type 1”when increased levels of serum IgG4 were present and other organs were involved;lymphoplasmacytic sclerosing pancreatitis was the main histological characteristic.Apart from surgery,endoscopic ultrasonographyguided fine needle aspiration(EUS-FNA)is the only method for the histological diagnosis of AIP;however,this method is difficult.The use of larger-diameter FNA needles and trucut biopsy did not improve the diagnostic performance of EUS-FNA,but it has improved gradually.In this review,we look back at past efforts to improve the diagnostic performance of EUS-FNA and reveal the present state of EUS-FNA for the histological diagnosis of AIP type 1. 展开更多
关键词 AUTOIMMUNE PANCREATITIS TYPE 1 Endoscopic ultrasonography-guided fine needle ASPIRATION IgG4-related disease Lymphoplasmacytic SCLEROSING PANCREATITIS
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Experimental Study on PAT System for Long-Distance Laser Communications Between Fixed-Wing Aircrafts
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作者 Yao LEI Xiaoming LI Lizhong ZHANG 《光子传感器:英文版》 EI CAS CSCD 2019年第2期170-178,共9页
Free-space laser communication is characterized by high communication speed, strong anti-jamming ability, high confidentiality, and flexible configuration. In this paper, a pointing, acquisition, and tracking (PAT) sy... Free-space laser communication is characterized by high communication speed, strong anti-jamming ability, high confidentiality, and flexible configuration. In this paper, a pointing, acquisition, and tracking (PAT) system based on a two-stage (i.e., coarse and fine) composite tracking mechanism is proposed to solve the optical axis alignment problem, which is common in free-space laser communications. The acquisition probability of the PAT system is ensured by designing two tracking modules, a coarse tracking module which combines passive damping with active suppression and a fine tracking module based on an electromagnetic galvanometer. Both modules are combined by using a dynamic scanning mechanism based on the gyroscope signal. Finally, a free-space laser communication test with a long range and a high speed is conducted by two fixed-wing Y12 aircrafts equipped with the proposed PAT system. Experimental results show that the coarse tracking precision of the airborne PAT system is 10 μrad (1σ), and the fine tracking precision is 10μrad (1σ) during flights which are much improved as compared with the indoor tests. This indicates that the system can achieve a high precision for PAT during high-speed and long-range laser communications in the free-space. This also verifies the tracking capability and the environmental adaptability of the proposed laser communication PAT system. 展开更多
关键词 PAT SYSTEM laser COMMUNICATIONS airborne platform coarse TRACKING ERROR fine TRACKING ERROR
SIMULATED FINE STRUCTURES OF SPIRAL RAINBANDS IN TYPHOON CHANCHU(2006)
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作者 王咏青 蔡敏敏 葛旭阳 《热带气象学报:英文版》 SCIE 2019年第2期141-152,共12页
In this study, fine structures of spiral rainbands in super Typhoon Chanchu(2006) are examined using an Advanced Research Weather Research and Forecast(WRF-ARW) model simulation with the finest grid size of 2 km.Resul... In this study, fine structures of spiral rainbands in super Typhoon Chanchu(2006) are examined using an Advanced Research Weather Research and Forecast(WRF-ARW) model simulation with the finest grid size of 2 km.Results show that the simulation reproduces well Typhoon Chanchu’s track, intensity and basic structures. According to their locations and features, spiral rainbands are classified into principal, secondary, inner and distant rainbands, and their dynamic and thermodynamic features are investigated. The principal rainbands remain quasi-stationary with respect to Chanchu’s center and exhibit a wavenumber-1 feature with their outer edges separated by dry air. The secondary rainbands that occur on the radially inward side of the principal rainbands move around Chanchu’s center. The inner rainbands are closest to the center. They propagate both radially outward and azimuthally with time. The distant rainbands are located outside the inner-core region, and have stronger and continuous updrafts compared to the other rainbands. Distant rainbands are inward-sloping with height along the radial direction and have a cold pool in the low layers, whereas the principal and secondary rainbands lean radially outward with height. The inner rainbands do not show tilting with height along the radial direction. However, there are few vertical tilting cells along the azimuthal orientation among the four types of rainbands. The simulated radar reflectivity cores in all rainbands are collocated with the maxima of updrafts and equivalent potential temperatures in the low layer, indicating the important roles of energy supply in the boundary layer in determining the development of the rainband convection. 展开更多
关键词 TYPHOON SPIRAL RAINBANDS FINE STRUCTURES
Low temperature Pmmm and C2/m phases in Sr2CuO3+δ high temperature superconductor
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作者 王海波 罗震林 +5 位作者 杨远俊 刘清青 胡思侠 杨蒙蒙 靳常青 高琛 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第5期206-209,共4页
A new low temperature Pmmm (120 K) phase was found in high temperature superconductor Sr2CuO3+δ,which was indicated as a pure electronic phase by resonant x-ray diffraction at Cu K-edge.As shown by x-ray absorption f... A new low temperature Pmmm (120 K) phase was found in high temperature superconductor Sr2CuO3+δ,which was indicated as a pure electronic phase by resonant x-ray diffraction at Cu K-edge.As shown by x-ray absorption fine structure (EXAFS) and x-ray absorption near edge structure (XANES) at Cu K-edge,the strong charge density redistribution and local lattice fluctuations around Cu site at the onset of phase transition were due to the occurrence of superconductive coherence,the redistribution and fluctuation finished at Tc.Finally,the electron–lattice interaction was mainly elaborated to understand the superconductivity of Sr2CuO3+δ. 展开更多
关键词 RESONANT X-RAY diffraction X-RAY absorption fine structure MODULATED phase SUPERCONDUCTIVITY
Appropriate number of biliary biopsies and endoscopic retrograde cholangiopancreatography sessions for diagnosing biliary tract cancer 预览
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作者 Tadayuki Takagi Mitsuru Sugimoto +11 位作者 Rei Suzuki Naoki Konno Hiroyuki Asama Yuki Sato Hiroki Irie Ko Watanabe Jun Nakamura Hitomi Kikuchi Mika Takasumi Minami Hashimoto Takuto Hikichi Hiromasa Ohira 《世界胃肠内镜杂志:英文版(电子版)》 2019年第3期231-238,共8页
BACKGROUND Biliary ductal cancer(BDC) is a lethal disease;however, diagnosing BDC is challenging. Biliary biopsies are performed to pathologically diagnose BDC, but the appropriate parameters for biliary biopsy [numbe... BACKGROUND Biliary ductal cancer(BDC) is a lethal disease;however, diagnosing BDC is challenging. Biliary biopsies are performed to pathologically diagnose BDC, but the appropriate parameters for biliary biopsy [number of biliary biopsies, number of endoscopic retrograde cholangiopancreatography(ERCP) sessions, etc.] are unknown.AIM To clarify what constitutes an adequate method for biliary biopsy.METHODS In total, 95 patients who underwent endoscopic biliary biopsy without choledochoscopy and who were pathologically diagnosed with BDC were enrolled in this study. The patients were divided into two groups. Seventy-six patients who were diagnosed by biliary biopsy were defined as the positive group(P group), and nineteen patients who were not diagnosed by biliary biopsy were defined as the negative group(N group). The patient characteristics and ERCP-related procedures were compared between the P and N groups.RESULTS The numbers of ERCP sessions and biliary biopsies were significantly different between the two groups (ERCP sessions(one/two), P group 72/4 vs N group15/4, P value = 0.048;number of biliary biopsies, P group 2(1-6) vs N group 2(1-7), P value = 0.039)In a multivariate analysis, fewer than 2 ERCP sessions was an independent factor influencing the positivity of the biliary biopsies.CONCLUSION This study clarified that ERCP and biliary ductal biopsy should only be performed once. If biliary cancer is not pathologically diagnosed after the first ERCP session, other methods(Endoscopic ultrasonography-guided fine needle aspiration or choledochoscopy-guided biliary ductal biopsy) should be employed. 展开更多
关键词 BILIARY DUCTAL cancer BILIARY biopsy ENDOSCOPIC retrograde cholangiopancreatography ENDOSCOPIC ultrasonography-guided fine needle aspiration CHOLEDOCHOSCOPY
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Production of composites with high relative permittivity using the spouted bed technique
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作者 E. Eichner P.-K. Fischer +1 位作者 S. Heinrich GA Schneider 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第1期184-189,共6页
This contribution presents a new application of the spouted bed technique. The developed production process involves coating fine copper particles with a polymer in a spouted bed plant and then hot pressing the produc... This contribution presents a new application of the spouted bed technique. The developed production process involves coating fine copper particles with a polymer in a spouted bed plant and then hot pressing the produced granules to form a compact consisting of a copper–polymer composite with a high filling degree. The fabricated composites possess high relative permittivity, which is advantageous for the production of effective capacitors. With increasing filling degree of copper, the relative permittivity of the composites increased, with a maximum relative permittivity of 214 obtained for the composite containing 78.1 vol% copper. Such a high filling degree can be achieved with conductive particles without obtaining a conductive composite by using the spouted bed technology in the production process. The high relative permittivity results from the high filling degree of particles isolated by a polymer coating. 展开更多
关键词 Spouted BED HIGH RELATIVE PERMITTIVITY FINE PARTICLES Coating Metal-polymer composite
Effects of the ambient fine particulate matter(PM2.5) exposure on urinary metabolic profiles in rats using UPLC-Q-TOF-MS
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作者 Lin Zhang Tengfei Xu +3 位作者 Zifeng Pi Meizhu Zheng Fengrui Song Zhiqiang Liu 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第1期90-94,共5页
In order to study the damage of ambient fine particulate matter(PM2.5) to organism in the environment,the method of urinary metabolomics was used to detect the potential endogenous metabolites and their related metabo... In order to study the damage of ambient fine particulate matter(PM2.5) to organism in the environment,the method of urinary metabolomics was used to detect the potential endogenous metabolites and their related metabolic pathways to clarify the toxicity mechanisms. Particles of PM2.5 collected from the fibrous membrane were extracted ultrasonically and dissolved in physiological saline to prepare PM2.5 suspension. The solution of saline and fine particular matter was injected into the trachea of rats respectively. The rats were injected two times a week for four weeks. Samples of 24-h urine were collected at the 14 th day after the end of exposure, and the ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used for the metabolomics detection. Principal component analysis(PCA) was used to investigate the global metabolomic alterations and a clear separation in the scatter diagram were observed. 17 potential endogenous metablites were identified from urinary samples in rats by UPLC-Q-TOF-MS. The primary metabolism pathways involved pentose and glucuronate interconversions, starch and sucrose metabolism, tryptophan metabolism, tyrosine metabolism, phenylalanine metabolism, purine metabolism, acetaminophen metabolism pathway, retinol metabolism and valproic acid metabolism pathway.The results are helpful to understand the toxicological mechanisms of PM2.5 and screened out potential biomarkers of rats which exposure to PM2.5. 展开更多
关键词 AMBIENT fine PARTICULATE MATTER UPLC -Q-TOF-MS Metabolomics URINE
新医改环境下的高值耗材精细化管理研究 预览
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作者 喻瑾 张凤勤 +4 位作者 陈默蓉 刘洋 杨涵 张涵 王雯萱 《中国医学装备》 2019年第6期122-126,共5页
目的:探索符合现代医院管理的高值耗材二次遴选制度和宏观调控制度,为高值耗材管理提供精细化管理新模式。方法:基于高值耗材供应链管理,依托高值耗材科学化管理流程与制度、完备的监督机制、二次遴选制度、供应商规范管理和人员素质培... 目的:探索符合现代医院管理的高值耗材二次遴选制度和宏观调控制度,为高值耗材管理提供精细化管理新模式。方法:基于高值耗材供应链管理,依托高值耗材科学化管理流程与制度、完备的监督机制、二次遴选制度、供应商规范管理和人员素质培养等探索高值耗材采购及二次遴选制度;从高值耗材的入库与出库、物资管理系统、二级库管理、信息化管理、货票同行、ABC分析法及耗材发放以及实时监管等加强高值耗材出入库管理和实时监管。结果:高值耗材二次遴选和二级库管理模式,可实现医用高值耗材的统一管理,让高值耗材管理由被动变主动,将简单粗放的管理提升为科学精细的管理,实现高值耗材采购及使用全过程的有效监管;高值耗材的宏观调控,依托数据分析,定期总结,可做到早期预警、中期控制和后期调整,规范高值耗材使用,降低卫生材料占比。结论:高值耗材的精细化管理可提升耗材合理、安全使用的综合水平,保障患者合法权益,降低患者医疗费用。 展开更多
关键词 新医改 精细化 控费 耗材调控 耗材使用监管
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Assessment of biomass and net primary productivity of a dry tropical forest using geospatial technology 预览
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作者 Tarun Kumar Thakur S.L.Swamy +1 位作者 Arvind Bijalwan Mammohan J.R.Dobriyal 《林业研究:英文版》 CAS CSCD 2019年第1期157-170,共14页
This study quantifies biomass,aboveground and belowground net productivity,along with additional environmental factors over a 2–3 year period in Barnawapara Sanctuary of Chhattisgarh,India through satellite remotesen... This study quantifies biomass,aboveground and belowground net productivity,along with additional environmental factors over a 2–3 year period in Barnawapara Sanctuary of Chhattisgarh,India through satellite remotesensing and GIS techniques.Ten sampling quadrates 20×20,5×5 and 1×1 m were randomly laid for overstorey(OS),understorey(US)and ground vegetation(GS),respectively.Girth of trees was measured at breast height and collar diameters of shrubs and herbs at 0.1 m height.Biomass was estimated using allometric regression equations and herb biomass by harvesting.Net primary productivity(NPP)was determined by summing biomass increment and litter crop values.Aspect and slope influenced the vegetation types,biomass and NPP in different forests.Standing biomass and NPP varied from 18.6 to 101.5 Mg ha^-1 and 5.3 to 12.7 Mg ha^-1 a^-1,respectively,in different forest types.The highest biomass was found in dense mixed forest,while net production recoded in Teak forests.Both were lowest in degraded mixed forests of different forest types.OS,US and GS contributed 90.4,8.7 and 0.7%,respectively,for the total mean standing biomass in different forests.This study developed spectral models for the estimation of biomass and NPP using Normalized Difference Vegetation Index and other vegetation indices.The study demonstrated the potential of geospatial tools for estimation of biomass and net productivity of dry tropical forest ecosystem. 展开更多
关键词 ALLOMETRIC regression equations Fine root BIOMASS LITTER FALL LAI NDVI SPECTRAL models
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我国精细硫磷化工的发展现状及展望 预览
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作者 赵红林 《硫酸工业》 CAS 2019年第1期1-10,共10页
介绍了我国精细硫磷化工产业的发展现状及未来发展的展望。我国硫磷化工行业尚处于世界硫磷产业链的中低端,大多采用粗放式资源利用生产基础化学品,中高端的精细硫化工和磷酸盐产品尚未形成产业链和规模效应。我国精细化工正处于绿色清... 介绍了我国精细硫磷化工产业的发展现状及未来发展的展望。我国硫磷化工行业尚处于世界硫磷产业链的中低端,大多采用粗放式资源利用生产基础化学品,中高端的精细硫化工和磷酸盐产品尚未形成产业链和规模效应。我国精细化工正处于绿色清洁工艺革新的关键时期,充分利用好硫、磷、氨、蒸汽等资源,实施产销研用一体化攻关,拓展高端精细硫磷化学品产业链,对破解传统硫磷化工发展瓶颈具有重大的意义。 展开更多
关键词 精细 硫化工 磷化工 现状 产业链 绿色清洁工艺
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