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含何首乌的中药滋肾育胎丸对犬的慢性肝脏毒性研究 被引量:5
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作者 骆永伟 崇立明 +3 位作者 李雷 黄秋玲 周莉 孙祖越 《中国中药杂志》 CAS CSCD 北大核心 2018年第15期3184-3191,共8页
研究含药典推荐剂量制何首乌的中药滋肾育胎丸对正常比格犬的慢性肝脏毒性。给药组犬分别灌胃给予低、中、高剂量组(1.5,3.0,6.0 g·kg^-1)的滋肾育胎丸,同时给予同体积的去离子水作为溶媒对照组,每天1次,共39周。给药期间每天观... 研究含药典推荐剂量制何首乌的中药滋肾育胎丸对正常比格犬的慢性肝脏毒性。给药组犬分别灌胃给予低、中、高剂量组(1.5,3.0,6.0 g·kg^-1)的滋肾育胎丸,同时给予同体积的去离子水作为溶媒对照组,每天1次,共39周。给药期间每天观察动物的一般状况,并于给药前、给药13,26,39,43周采血,测定犬血清肝脏毒性相关的生物标志;于给药13,39,43周后分别解剖雌雄各2/7,3/7,2/7只动物,观察动物脏器病变、称量主要脏器质量并对肝脏进行病理检查。结果发现与溶媒对照组相比,给药3,6,9个月和恢复期1个月,各给药组比格犬AST,ALT等11项肝毒性传统生物标志均未见与受试物有关的变化;肝脏脏器指数和肝脏病理学检查均未见明显异常。因此,正常比格犬连续9个月灌胃给予滋肾育胎丸,剂量分别为1.5,3.0,6.0 g·kg^-1,未见明显慢性肝脏毒性。 展开更多
关键词 滋肾育胎丸 制何首乌 肝毒性 比格犬
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中国古代先民遗骸人工改形的发现与研究 被引量:3
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作者 李海军 刘力铭 +1 位作者 张一丹 肖小勇 《人类学学报》 CSSCI CSCD 北大核心 2023年第4期540-553,共14页
对古代先民遗骸人工改形的研究,有助于了解古代文化习俗、审美取向、医疗技术,间接了解古代社会的组织结构、等级分化等;研究人工改形的起源、传播,还能揭示不同地区、族群之间的文化交流与碰撞。我国目前发现的古代先民遗骸人工改形类... 对古代先民遗骸人工改形的研究,有助于了解古代文化习俗、审美取向、医疗技术,间接了解古代社会的组织结构、等级分化等;研究人工改形的起源、传播,还能揭示不同地区、族群之间的文化交流与碰撞。我国目前发现的古代先民遗骸人工改形类型丰富,但是相关研究成果缺乏整体性总结。因此,本文尝试系统梳理先民遗骸人工改形现象的相关案例,总结其主要类型、特点及相关学术争论,从民族学视角分析研究人工改造痕迹的借鉴价值,并对人工改形的研究意义进行阐释。 展开更多
关键词 先民 遗骸 改造痕迹 民族考古
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适用于再生编码分布式存储的轻量型隐私保护审计方案 被引量:5
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作者 刘光军 郭网媚 +2 位作者 熊金波 刘西蒙 董长宇 《通信学报》 EI CSCD 北大核心 2021年第7期220-230,共11页
为了降低面向再生编码分布式存储系统的外包数据审计机制的安全实现开销,提出了一种正交化代数编码方法,以此构造一类基于线性同态认证的轻量型隐私保护审计方案。利用文件编码数据与私有密钥向量的正交化构造外包存储向量的同态认证标... 为了降低面向再生编码分布式存储系统的外包数据审计机制的安全实现开销,提出了一种正交化代数编码方法,以此构造一类基于线性同态认证的轻量型隐私保护审计方案。利用文件编码数据与私有密钥向量的正交化构造外包存储向量的同态认证标签,并提出利用密钥特定分量的正交基向量组的随机化掩码来完成审计响应消息的隐私保护,实现代数编码、隐私保护和安全审计的高效融合。理论分析表明,所提方案在再生编码分布式存储应用中可实现信息理论意义下的安全性。与现有同类工作相比,该方案计算复杂度低,通信开销小,具有更好的性能优势。 展开更多
关键词 数据审计 隐私保护 再生码 网络编码 分布式存储
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6G与太赫兹通信技术导读 被引量:2
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作者 刘光毅 陈智 《无线电通信技术》 北大核心 2024年第1期32-33,共2页
内容导读太赫兹波是0.1~10 THz频段的电磁波,对应波长3~0.03 mm,介于毫米波和红外光之间。太赫兹频段具有丰富的频谱资源,可用于地面短距离高速无线通信和空间卫星通信,被认为是6G候选频段之一。目前,太赫兹通信作为6G潜在关键技术之一... 内容导读太赫兹波是0.1~10 THz频段的电磁波,对应波长3~0.03 mm,介于毫米波和红外光之间。太赫兹频段具有丰富的频谱资源,可用于地面短距离高速无线通信和空间卫星通信,被认为是6G候选频段之一。目前,太赫兹通信作为6G潜在关键技术之一,已成为移动通信领域学术界和工业界的研究热点。其中,涉及太赫兹通信硬件系统设计、太赫兹器件研制、宽频信号的高效调制与处理、信道测量和建模技术、信道编码技术、通信感知一体化技术、智能反射面辅助技术、超大规模天线技术等大量关键科学技术与工程设计问题。 展开更多
关键词 太赫兹通信 信道编码技术 硬件系统设计 太赫兹器件 移动通信领域 信道测量 卫星通信 毫米波
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多端交通视频分析任务卸载决策 被引量:1
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作者 温震宇 胡慧峰 +2 位作者 钱滨 洪榛 俞立 《控制与决策》 EI CSCD 北大核心 2024年第8期2773-2782,共10页
针对智慧交通中多点位监控视频分析时出现的计算任务繁重、设备之间资源利用不均衡的问题,提出一种基于云控制的视频分析卸载方案.首先,针对客户端算力不足而无法完成视频分析任务的问题,使用一种视频卸载框架,将部分视频分析任务切块... 针对智慧交通中多点位监控视频分析时出现的计算任务繁重、设备之间资源利用不均衡的问题,提出一种基于云控制的视频分析卸载方案.首先,针对客户端算力不足而无法完成视频分析任务的问题,使用一种视频卸载框架,将部分视频分析任务切块卸载至云服务器处理;其次,针对服务器与多客户端之间的算力资源竞争问题,提出一种阶段优化卸载算法,平衡设备之间负荷,提高资源利用率;最后,针对不同点位的客户端需求不同的问题,在算法中加入精度和能耗偏好,满足不同客户端的需求.与其他卸载方案对比的实验表明,所提出方案能够更好地对视频分析任务进行合理分配,提高系统收益,并通过扩展实验验证所提出系统的扩展能力. 展开更多
关键词 多端 视频分析 任务卸载 资源竞争 卸载决策 智慧交通
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碳十四测年技术前沿:新一代校正曲线IntCal20发布 被引量:5
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作者 刘睿良 理查德·斯达夫 《江汉考古》 CSSCI 北大核心 2020年第5期121-128,共8页
碳十四目前已经成为考古领域应用最为广泛的科技测年手段,但是任何碳十四数据转化为实际日历年份都离不开校正曲线。2020年,最新碳十四校正曲线正式发布,再一次引起了各个学科的广泛关注与讨论。对于考古学界而言,最关心的问题莫过于新... 碳十四目前已经成为考古领域应用最为广泛的科技测年手段,但是任何碳十四数据转化为实际日历年份都离不开校正曲线。2020年,最新碳十四校正曲线正式发布,再一次引起了各个学科的广泛关注与讨论。对于考古学界而言,最关心的问题莫过于新发布的碳十四校正曲线是否会对已有年代序列造成影响。本文通过定性定量等方法细致对比了北半球新旧两条校正曲线(IntCal20和IntCal13),发现二者主要的区别存在于30000 BP之前和11000-10000 BP这两个大的时间范围内,而对于碳十四数据相对集中的中国新石器和青铜时代之年代框架影响甚微。 展开更多
关键词 考古学界 碳十四 青铜时代 校正曲线 数据转化 年代序列 年代框架 技术前沿
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Removal of Cu(II), Pb(II) and Zn(II) Ions from Aqueous Solutions Using Selected Agricultural Wastes: Adsorption and Characterisation Studies 被引量:8
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作者 Siti Najiah Mohd Yusoff Azlan Kamari +4 位作者 Wiwid Pranata Putra Che Fauziah Ishak Azmi Mohamed Norhayati Hashim Illyas Md Isa 《Journal of Environmental Protection》 2014年第4期289-300,共12页
The feasibility of durian tree sawdust (DTS), coconut coir (CC) and oil palm empty fruit bunch (EFB) as low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. T... The feasibility of durian tree sawdust (DTS), coconut coir (CC) and oil palm empty fruit bunch (EFB) as low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. The effects of solution pH and initial metal concentration on adsorption capacity were examined in batch experiments. The affinity and the adsorption capacity of DTS, CC and EFB were evaluated. The adsorption behaviour of Cu(II), Pb(II) and Zn(II) ions onto DTS, CC and EFB was described using Freundlich and Langmuir isotherm models. The separation factor (RL) analysis suggests that the removal of metal ions onto three agricultural wastes studied was favourable. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 18.42, 20.37 and 22.78 mg/g for DTS, 18.38, 37.04 and 24.39 mg/g for CC, and 26.95, 37.59 and 21.19 mg/g for EFB, respectively. The characterisation studies were carried out using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). The surface morphology of the biosorbents changed significantly following interaction with metal ions. The primary adsorption mechanism was complexation between metal ions and binding sites of biosorbents. Both hydroxyl and amine groups are the main binding sites in DTS, CC and EFB. 展开更多
关键词 ADSORPTION Characterisation Metals DURIAN Tree SAWDUST Coconut COIR Oil Palm Empty Fruit Bunch
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Evaluation of Fractionation of Softwood Pulp in a Cylindrical Hydrocyclone 被引量:4
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作者 卢晓江 刘世杰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4期537-541,共5页
Pulp fiber length characterization is addressed in this article. It is .suggested that the proposed separation index H(L) is a viable index to the fiber fractionation performance for evaluating hydrocyclones. Fracti... Pulp fiber length characterization is addressed in this article. It is .suggested that the proposed separation index H(L) is a viable index to the fiber fractionation performance for evaluating hydrocyclones. Fractionation of softwood (coniferous wood) bleached chemithermomechanical pulp (BCTMP) fiber was carried out with a cylindrical hydrocyclone. Pulp fiber length characteristics in different streams were examined using the fiber quality analyzer (FQA), and the cumulative fiber length fraction, the fiber length fraction density function and the separation index H(L) for different streams were obtained. It is found that H(L) is very useful for characterizing the fiber fractionation performance by indicating the separation capacity of hydrocyclone for individual subgroup of fibers in different streams under different operation conditions. Results of H(L) show that there exists a critical fiber length. A higher proportion of fibers longer than the critical fiber length is in the overflow stream, and a higher proportion of fibers shorter than the critical fiber length in the undertow stream. The data obtained from FQA suggest that the split ratio is the most significant parameter for fiber fractionation performance, which is the best when the split ratio is in the range between 0.14 and 0.2. The effect of feed rate on fiber fractionation performance is weak. 展开更多
关键词 EVALUATION FIBER FRACTIONATION HYDROCYCLONE
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Evaluation of Fractionation of Softwood Pulp in a Cylindrical Hydrocyclone 被引量:2
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作者 卢晓江 刘世杰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4X期537-541,共5页
Pulp fiber length characterization is addressed in this article. It is suggested that the proposed separation index H(L) is a viable index to the fiber fractionation performance for evaluating hydrocyclones. Fractiona... Pulp fiber length characterization is addressed in this article. It is suggested that the proposed separation index H(L) is a viable index to the fiber fractionation performance for evaluating hydrocyclones. Fractionation of softwood (coniferous wood) bleached chemithermomechanical pulp (BCTMP) fiber was carried out with a cylin- drical hydrocyclone. Pulp fiber length characteristics in different streams were examined using the fiber quality analyzer (FQA), and the cumulative fiber length fraction, the fiber length fraction density function and the separa- tion index H(L) for different streams were obtained. It is found that H(L) is very useful for characterizing the fiber fractionation performance by indicating the separation capacity of hydrocyclone for individual subgroup of fibers in different streams under different operation conditions. Results of H(L) show that there exists a critical fiber length. A higher proportion of fibers longer than the critical fiber length is in the overflow stream, and a higher proportion of fibers shorter than the critical fiber length in the underflow stream. The data obtained from FQA suggest that the split ratio is the most significant parameter for fiber fractionation performance, which is the best when the split ratio is in the range between 0.14 and 0.2. The effect of feed rate on fiber fractionation performance is weak. 展开更多
关键词 EVALUATION FIBER FRACTIONATION HYDROCYCLONE
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Biosorption of Cu(II), Pb(II) and Zn(II) Ions from Aqueous Solutions Using Selected Waste Materials: Adsorption and Characterisation Studies 被引量:5
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作者 Wiwid Pranata Putra Azlan Kamari +4 位作者 Siti Najiah Mohd Yusoff Che Fauziah Ishak Azmi Mohamed Norhayati Hashim Illyas Md Isa 《Journal of Encapsulation and Adsorption Sciences》 2014年第1期25-35,共11页
The efficacy of coconut tree sawdust (CTS), eggshell (ES) and sugarcane bagasse (SB) as alternative low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. Batch... The efficacy of coconut tree sawdust (CTS), eggshell (ES) and sugarcane bagasse (SB) as alternative low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. Batch adsorption studies were carried out to evaluate the effects of solution pH and initial metal concentration on adsorption capacity. The optimum biosorption condition was found at pH 6.0, 0.1 g biomass dosage and at 90 min equilibrium time. The adsorption data were fitted to the Freundlich and Langmuir isotherm models. The adsorption capacity and affinity of CTS, ES and SB were evaluated. The Freundlich constant (n) and separation factor (RL) values suggest that the metal ions were favourably adsorbed onto biosorbents. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 3.89, 25.00 and 23.81 mg/g for CTS, 34.48, 90.90 and 35.71 mg/g for ES, and 3.65, 21.28 and 40.00 mg/g for SB, respectively. The characterisation studies were performed using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). Interaction with metal ions led to the formation of discrete aggregates on the biosorbents surface. The metal ions bound to the active sites of the biosorbents through either electrostatic attraction or complexation mechanism. 展开更多
关键词 ADSORPTION Characterisation Metal IONS Coconut Tree SAWDUST EGGSHELL Sugarcane Bagasse
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Cancer Therapy Using Antibiotics 被引量:2
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作者 Biplob Bhattacharya Sreya Mukherjee 《Journal of Cancer Therapy》 2015年第10期849-858,共10页
Anticancer antibiotics have made a successful impact in the field of chemotherapeutics. For most of them, DNA is the molecular target. Some act as DNA intercalators or some prevent DNA repair among other mechanisms of... Anticancer antibiotics have made a successful impact in the field of chemotherapeutics. For most of them, DNA is the molecular target. Some act as DNA intercalators or some prevent DNA repair among other mechanisms of actions, they are seen to have. The major disadvantages of these drugs though are the constant side effects and toxicities. With more focus on discovery of new drugs with newer scaffolds, the urge to discover and modify anticancer antibiotics is being lost. Modifications or even the wider research can yield newer better drugs for clinical use. The review here discusses the current antibiotic therapeutics, newer discoveries in the field as well ideas for future research. 展开更多
关键词 ANTIBIOTICS LACTAMS CANCER MECHANISM of Action
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The Integration of Farmers and Nomads: Archaeological Evidence for the Human Subsistence Strategy in Northwestern China during the Han Dynasty 被引量:1
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作者 LI Xin LU Minxia +2 位作者 CUI Yifu LIU Ruiliang MA Minmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第3期603-611,共9页
The integration of farmers and nomads in northwestern China during the Han Dynasty(206 BCE ~ 220 CE) provides a crucial opportunity to reconstruct the material exchanges, formation and development of the Silk Road in ... The integration of farmers and nomads in northwestern China during the Han Dynasty(206 BCE ~ 220 CE) provides a crucial opportunity to reconstruct the material exchanges, formation and development of the Silk Road in antiquity. The subsistence strategy is arguably an effective proxy for the integration of various groups of people(e.g. farmers and nomads). In this paper, we have reported new stable isotope data from the Huangwan tombs dated to the Han dynasty in middle Gansu, which was the key juncture between the Han and Xiongnu empire, in order to fill the gap and further understand the substance strategies employed by the local people. According to the results of plant remains and stable isotopic data, millet farming, the typical agricultural activities for the Han Chinese in the Central Plains, was also the primary lifestyle for the Huangwan people in the mid Gansu. More importantly, this shows fundamentally remarkable difference from the agricultural practices in the Bronze Age Gansu Corridor, which were based on a variety of crops, including wheat, barley and millet. This major shift in the subsistence production at Huangwan can be correlated to a wider historical background in which the Han empire showed increasing political and military presence in the Gansu Corridor, indicating that local indigenous nomads followed the lifestyle of Han Chinese(e.g., millet farming), and/or the Han immigrates maintained millet farming. 展开更多
关键词 CARBON NITROGEN NOMADS Silk Road Han Chinese
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Asymmetric image encryption algorithm based on a new three-dimensional improved logistic chaotic map 被引量:1
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作者 叶国栋 吴惠山 +1 位作者 黄小玲 Syh-Yuan Tan 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期153-163,共11页
Based on some analyses of existing chaotic image encryption frameworks and a new designed three-dimensional improved logistic chaotic map(3D-ILM),an asymmetric image encryption algorithm using public-key Rivest–Shami... Based on some analyses of existing chaotic image encryption frameworks and a new designed three-dimensional improved logistic chaotic map(3D-ILM),an asymmetric image encryption algorithm using public-key Rivest–Shamir–Adleman(RSA)is presented in this paper.In the first stage,a new 3D-ILM is proposed to enhance the chaotic behavior considering analysis of time sequence,Lyapunov exponent,and Shannon entropy.In the second stage,combined with the public key RSA algorithm,a new key acquisition mathematical model(MKA)is constructed to obtain the initial keys for the 3D-ILM.Consequently,the key stream can be produced depending on the plain image for a higher security.Moreover,a novel process model(NPM)for the input of the 3D-ILM is built,which is built to improve the distribution uniformity of the chaotic sequence.In the third stage,to encrypt the plain image,a pre-process by exclusive OR(XOR)operation with a random matrix is applied.Then,the pre-processed image is performed by a permutation for rows,a downward modulo function for adjacent pixels,a permutation for columns,a forward direction XOR addition-modulo diffusion,and a backward direction XOR addition-modulo diffusion to achieve the final cipher image.Moreover,experiments show that the the proposed algorithm has a better performance.Especially,the number of pixels change rate(NPCR)is close to ideal case 99.6094%,with the unified average changing intensity(UACI)close to 33.4634%,and the information entropy(IE)close to 8. 展开更多
关键词 three-dimensional improved logistic chaotic map(3D-ILM) Rivest–Shamir–Adleman(RSA)algorithm image encryption CONFUSION ENTROPY
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Preparation of Fish Scales Hydroxyapatite (FsHAp) for Potential Use as Fillers in Polymer 被引量:2
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作者 Alhussein Arkan Majhooll Ismail Zainol +4 位作者 Che Nor Aiza Jaafar Mustafa Mudhafar Alsailawi H.A. Abbas Asaad Fouad WMezaal 《Journal of Chemistry and Chemical Engineering》 2019年第3期97-104,共8页
The aims of this study were to prepare natural hydroxyapatite from fish scales(FsHAp)for potential use as a filler in polymer.The FsHAp was prepared from Tilapia fish scales using thermal method.The FsHAp was milled f... The aims of this study were to prepare natural hydroxyapatite from fish scales(FsHAp)for potential use as a filler in polymer.The FsHAp was prepared from Tilapia fish scales using thermal method.The FsHAp was milled for 48 h and dried by spray method.The morphology was characterized using field emission scanning electron microscope(FESEM)which showed irregular shape of FsHAp particles with particle size around 7μm.The analysis of FsHAp was carried out using Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)to confirm chemical structure of FsHAp. 展开更多
关键词 HYDROXYAPATITE POLYMER FILLERS fish scales
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Physicochemical and environmental characteristics of alkali leaching residue of wolframite and process for valuable metals recovery 被引量:2
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作者 Yuan-lin CHEN Xue-yi GUO +3 位作者 Qin-meng WANG Qing-hua TIAN Jin-xiang ZHANG Shao-bo HUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第5期1638-1649,共12页
Physicochemical and mineralogical characteristics of an alkali leaching residue of wolframite were studied by XRD,SEM−EDS,chemical phase analysis,mineral liberation analyzer(MLA),and TG−DSC methods.Batch leaching test... Physicochemical and mineralogical characteristics of an alkali leaching residue of wolframite were studied by XRD,SEM−EDS,chemical phase analysis,mineral liberation analyzer(MLA),and TG−DSC methods.Batch leaching tests,toxicity characteristic leaching procedure(TCLP)tests and Chinese standard leaching tests(CSLT)were conducted to determine the environmental mobility of toxic elements.The results show that,due to the high contents of W,Fe,Mn,Sn,and Nb,the residue is with high resource value,but the content of a toxic element,As,is also high.The existing minerals of the investigated elements mainly occur as monomer particles,but it is difficult to extract these valuable metals by conventional acid leaching due to their mineral properties.The release of As increases over time in acidic environment.The leaching concentration of all investigated harmful elements through TCLP is within the limiting value,while the leaching concentration of As through CSLT exceeds the limiting value by more than 4 times,so the residue is classified as hazardous solid waste based on the Chinese standard.A process for valuable metals recovery from this residue was proposed.Preliminary experimental results indicated that the main valuable metals could be extracted effectively. 展开更多
关键词 alkali leaching residue physicochemical characteristics environmental characteristics valuable metals recovery
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Climate change and contrasting plasticity in timing of a two-step migration episode of an Arctic-nesting avian herbivore 被引量:3
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作者 Anthony David FOX Mitch D.WEEGMAN +4 位作者 Stuart BEARHOP GeoffM.HILTON Larry GRIFFIN David A.STROUD Alyn WALSH 《Current Zoology》 SCIE CAS CSCD 2014年第2期233-242,共10页
Greenland white-fronted geese Anser albifrons flavirostris wintering in Britain and Ireland migrate over the sea for 700-1200 km to stage 3-5 weeks in Iceland in spring, continuing a similar distance over the sea and ... Greenland white-fronted geese Anser albifrons flavirostris wintering in Britain and Ireland migrate over the sea for 700-1200 km to stage 3-5 weeks in Iceland in spring, continuing a similar distance over the sea and Greenland Ice Cap to West Greenland breeding grounds. During 1969 to 2012, the geese advanced the mean departure date from Ireland by 15 days, during which time also they attained threshold fat stores earlier as well as departing in fatter condition. Over that period, Iceland spring-staging geese shifted from consuming underground plant storage organs to grazing managed hayfields, which provide fresh grass growth despite sub-zero temperatures, when traditional natural foods are inaccessible in frozen substrates. In 2012 and 2013, geese arrived three weeks earlier to Iceland, in fatter condition and accumulated fat significantly slower than in 1997-1999 and 2007. Although geese accumulated sufficient fat stores earlier in Iceland in 2007, 2012 and 2013, they departed around the same date as in 1997-1999, prolonging spring staging by three weeks. Plasticity in winter departure dates is likely due to improved winter feeding conditions (enabling earlier departure in better condition) and a novel predictable food resource in Iceland. Greenland white-fronted geese attained threshold fat stores in Iceland earlier, but remained rather than departing earlier to Greenland. Despite arriving earlier in Iceland, arrival dates on the breeding areas have not changed since the 1880s, presumably because of relatively constant cool springs and heavy snowfall in West Greenland during recent years [Current Zoology 60 (2): 233-242, 2014]. 展开更多
关键词 Anser albifronsflavirostris Climate mismatch Greenland white-fronted geese Migration phenology Vernalmigration
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激光打孔技术在光伏背板玻璃上的应用 被引量:3
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作者 林加富 《玻璃》 2022年第2期53-57,共5页
双玻光伏组件以其抗PID性强、防隐裂、防水汽透过、抗蜗牛纹、可靠性优异、轻量化等诸多优点,在晶硅太阳能组件市占比逐步提高。双玻光伏组件用背板玻璃一般需要预留出线孔,光伏背板玻璃的出线孔主要有两种打孔方式:金钢钻上下同步钻孔... 双玻光伏组件以其抗PID性强、防隐裂、防水汽透过、抗蜗牛纹、可靠性优异、轻量化等诸多优点,在晶硅太阳能组件市占比逐步提高。双玻光伏组件用背板玻璃一般需要预留出线孔,光伏背板玻璃的出线孔主要有两种打孔方式:金钢钻上下同步钻孔的模式和激光打孔。激光打孔以其易维护、可异形孔加工、效率高、生产成本低等优势得到各大玻璃厂的认可。通过分析在实际生产中激光打孔出现的打孔缺陷问题,提出了改善措施,有助于工厂的降本增效。 展开更多
关键词 激光打孔 光伏玻璃 双玻组件 背板
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Outcomes of pregnancy in patients with known Budd-Chiari syndrome 被引量:1
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作者 Faisal Khan Ian Rowe +9 位作者 Bill Martin Ellen Knox Tracey Johnston Charlie Elliot Will Lester Frederick Chen Simon Olliff Homoyon Mehrzad Zergham Zia Dhiraj Tripathi 《World Journal of Hepatology》 CAS 2017年第21期945-952,共8页
AIM To analyse the risk of pregnancy(a prothrombotic state)in patients with Budd-Chiari Syndrome(BCS).METHODS Retrospective study of pregnancy in women with known BCS at single center from January 2001 to December 201... AIM To analyse the risk of pregnancy(a prothrombotic state)in patients with Budd-Chiari Syndrome(BCS).METHODS Retrospective study of pregnancy in women with known BCS at single center from January 2001 to December 2015.RESULTS Out of 53 females with BCS,7 women had 16 pregnancies.Median age at diagnosis of BCS in these women was 25 years(range 21-34 years).At least one causal factor for BCS was identified in 6 women(86%).Six women had undergone radiological decompressive treatment.All patients had anticoagulation.Six fetuses were lost before 20 wk gestation in 2 women.There were 9 deliveries over 32 wk gestation and one delivery at 27 wk.All infants did well.Seven babies were born by emergency caesarean section.There were no cases of thrombosis.Two patients had notable vaginal(PV)bleeding in 3 pregnancies.None of the patients had variceal haemorrhage.Two patients were diagnosed with pulmonary hypertension,one during pregnancyand the other in the post-partum period.There was no maternal mortality.CONCLUSION Maternal outcomes in patients with treated BCS are favourable and fetal outcomes beyond 20 wk gestation are good.There has been increased rate of caesarean section.Pulmonary hypertension is an important finding that needs further validation.These patients should be managed in centers experienced in treating high-risk pregnancies. 展开更多
关键词 Budd-Chiari syndrome PREGNANCY Portal hypertension Pulmonary hypertension THROMBOPHILIA
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采矿保护区:世界保护联盟的观点 被引量:1
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作者 臧立杰 Adrian Phillips 《产业与环境》 2001年第S1期90-91,共2页
关键词 世界保护联盟 生物多样性保护 护区 环境影响评价 采矿活动 负面影响 世界遗产委员会 可持续 利益攸关者 矿物资源
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Blockade of CD300A enhances the ability of human NK cells to lyse hematologic malignancies 被引量:1
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作者 Shuangcheng Li Tianci Wang +6 位作者 Xinghui Xiao Xiaodong Zheng Haoyu Sun Rui Sun Hongdi Ma Zhigang Tian Xiaohu Zheng 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第4期331-346,共16页
Objective: The human cluster of differentiation(CD)300A, a type-I transmembrane protein with immunoreceptor tyrosine-based inhibitory motifs, was investigated as a potential immune checkpoint for human natural killer(... Objective: The human cluster of differentiation(CD)300A, a type-I transmembrane protein with immunoreceptor tyrosine-based inhibitory motifs, was investigated as a potential immune checkpoint for human natural killer(NK) cells targeting hematologic malignancies(HMs).Methods: We implemented a stimulation system involving the CD300A ligand, phosphatidylserine(PS), exposed to the outer surface of malignant cells. Additionally, we utilized CD300A overexpression, a CD300A blocking system, and a xenotransplantation model to evaluate the impact of CD300A on NK cell efficacy against HMs in in vitro and in vivo settings. Furthermore, we explored the association between CD300A and HM progression in patients.Results: Our findings indicated that PS hampers the function of NK cells. Increased CD300A expression inhibited HM lysis by NK cells. CD300A overexpression shortened the survival of HM-xenografted mice by impairing transplanted NK cells. Blocking PS–CD300A signals with antibodies significantly amplified the expression of lysis function-related proteins and effector cytokines in NK cells, thereby augmenting the ability to lyse HMs. Clinically, heightened CD300A expression correlated with shorter survival and an “exhausted” phenotype of intratumoral NK cells in patients with HMs or solid tumors.Conclusions: These results propose CD300A as a potential target for invigorating NK cell-based treatments against HMs. 展开更多
关键词 NK cell CD300A PHOSPHATIDYLSERINE immune checkpoint hematologic malignancy
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