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溶剂热法制备Fe^(2+)掺杂LiCoPO_(4)及其电极性能
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作者 李志义 王成伟 +3 位作者 孙海礼 魏炜 刘凤霞 刘志军 《精细化工》 北大核心 2026年第1期42-49,59,共9页
以一水合氢氧化锂、四水合醋酸钴为原料,采用抗坏血酸辅助的温和溶剂热法制备了LiCoPO_(4)前驱体,再经煅烧后制备了LiCoPO_(4),最后制备了不同Fe^(2+)掺杂量(x)的LiCo_(1–x)Fe_(x)PO_(4)。通过XRD、SEM表征和电化学性能测试,考察了溶... 以一水合氢氧化锂、四水合醋酸钴为原料,采用抗坏血酸辅助的温和溶剂热法制备了LiCoPO_(4)前驱体,再经煅烧后制备了LiCoPO_(4),最后制备了不同Fe^(2+)掺杂量(x)的LiCo_(1–x)Fe_(x)PO_(4)。通过XRD、SEM表征和电化学性能测试,考察了溶剂热反应时间、煅烧温度和Fe^(2+)掺杂量对LiCoPO_(4)及LiCo_(1–x)Fe_(x)PO_(4)形貌和作为正极材料性能的影响。结果表明,对溶剂热反应时间与煅烧温度的调控可以实现LiCoPO_(4)的形貌和颗粒粒径的优化,进而改善其电化学性能。在溶剂热反应时间为9 h、煅烧温度为700℃的条件下可制备出形貌为板状的LiCoPO_(4)颗粒,其首次放电比容量达到163.21 mA·h/g;当x=0.09时,LiCo_(0.91)Fe_(0.09)PO_(4)表现出最佳的循环性能和倍率性能,在0.1 C倍率下经过30次循环,LiCo_(0.91)Fe_(0.09)PO_(4)与未经Fe^(2+)掺杂的LiCoPO_(4)相比,放电比容量从52.12 mA·h/g提升至111.75 mA·h/g,容量保留率由31.93%提升至77.66%。 展开更多
关键词 磷酸钴锂 溶剂热法 抗坏血酸 形貌 电化学性能 Fe^(2+)掺杂 功能材料
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猪圆环病毒2型微滴数字PCR检测方法的建立及临床应用
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作者 刘武函 唐小明 +8 位作者 彭志 张坤 谢怡灵 范仲鑫 王卫国 尚玲 张梦凡 杨青 胡巧云 《黑龙江畜牧兽医》 北大核心 2026年第1期120-125,共6页
为建立一种特异性强、敏感性高、重复性好的猪圆环病毒2型(PCV-2)微滴数字PCR检测方法,试验基于PCV-2 ORF1保守区域设计引物和探针,通过优化引物浓度、探针浓度和退火温度及特异性、敏感性和重复性试验建立微滴数字PCR方法,并采用该方法... 为建立一种特异性强、敏感性高、重复性好的猪圆环病毒2型(PCV-2)微滴数字PCR检测方法,试验基于PCV-2 ORF1保守区域设计引物和探针,通过优化引物浓度、探针浓度和退火温度及特异性、敏感性和重复性试验建立微滴数字PCR方法,并采用该方法对90份临床样本进行检测。结果表明:建立的PCV-2微滴数字PCR检测方法的最佳引物和探针浓度分别为18μmol/L和9μmol/L,退火温度为61℃;能特异性检出PCV-2,与多种常见猪病原[猪圆环病毒3型(PCV-3)、伪狂犬病毒(PRV)、猪繁殖与呼吸综合征病毒(PRRSV)、非洲猪瘟病毒(ASFV)、猪瘟病毒(CSFV)和猪流行性腹泻病毒(PEDV)]无交叉反应;最低检测限为3.48 copies/μL;重复性试验中扩增后的拷贝数组内与组间变异系数范围分别在0.91%~6.13%和1.44%~8.53%之间,均小于10%。90份临床样本中,建立的微滴数字PCR方法检出PCV-2阳性样本43份,检出率为47.78%,经统计微滴数字PCR方法检出的阳性样本包含了实时荧光定量PCR方法检出的所有阳性样本,与实时荧光定量PCR方法的符合率为88.89%。说明本研究建立的PCV-2微滴数字PCR检测方法特异性强、敏感性高、重复性好,适用于临床样本(特别是低病毒载量样本)的检测。 展开更多
关键词 猪圆环病毒2 微滴数字PCR 病毒检测 检测方法 特异性试验 敏感性试验 重复性试验
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Synthesis of Nano-CuF_(2) with Superior Electrochemical Performances via a Mixed Solvent Coprecipitation Method
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作者 DU Suni YU Zhiyong +5 位作者 JI Erte XU Hanchen ZHAO Yichun LIU Hanxing LAI Caiting YUAN Zhongzhi 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1206-1212,共7页
Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced eff... Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced effect on both the particle size and the extent of agglomeration.With the increase in methanol content,the particle size and agglomeration of CuF_(2) decreased first and then increased.When the volume ratio of methanol to deionized water was 1:1,the CuF_(2) particles exhibited the smallest size and the lowest degree of agglomeration.CuF_(2) synthesized with 50%methanol exhibited superior electrochemical performances with a voltage plateau above 3 V and a 1st discharge capacity of 525.8 mAh·g^(-1) at 0.01 C due to the synergistic influence of the particle size and dispersion.The analysis results using electrochemical impedance spectroscopy(EIS)and constant current intermittent titration technique(GITT)affirmed the addition of methanol was beneficial for promoting Li+diffusion and accelerating electrochemical reaction kinetics of CuF_(2). 展开更多
关键词 CuF_(2) lithium-ion battery mixed solvent co-precipitation method electrochemical performances
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CO_(2)捕集用胺基吸收剂的研究进展
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作者 李珍珍 徐冬 +3 位作者 杭晨哲 杜庶铭 刘扬 潘冠福 《低碳化学与化工》 北大核心 2026年第1期120-131,共12页
开展CO_(2)捕集是缓解化石能源利用与全球变暖问题之间矛盾的有效途径,胺基吸收剂是CO_(2)捕集(化学吸收法)的主要材料。介绍了胺基吸收剂捕集CO_(2)的机理,对比了不同胺基吸收剂的构成特征及其CO_(2)捕集性能。单组分胺吸收剂制备工艺... 开展CO_(2)捕集是缓解化石能源利用与全球变暖问题之间矛盾的有效途径,胺基吸收剂是CO_(2)捕集(化学吸收法)的主要材料。介绍了胺基吸收剂捕集CO_(2)的机理,对比了不同胺基吸收剂的构成特征及其CO_(2)捕集性能。单组分胺吸收剂制备工艺简单,但存在CO_(2)吸收容量低(0.50~0.53 mol/mol)、再生能耗高(3.5~4.0 GJ/t)等问题。通过引入其他吸收剂形成混合胺吸收剂,可将CO_(2)吸收容量提高至0.706 mol/mol(2-氨基-2-甲基-1-丙醇和N-甲基-4-哌啶醇),并可降低再生能耗、提高经济性。两相吸收剂因仅需加热富相部分,再生能耗低至1.61 GJ/t(2-氨基-2-甲基-1-丙醇/哌嗪/乙二醇二甲醚),且具有较好的稳定性,发展前景良好。少水(无水)吸收剂在CO_(2)吸收容量方面优势突出,但吸收速率较慢,再生能耗达2.365 GJ/t(二乙烯三胺-三乙醇胺)。以离子液体吸收剂为代表的新型吸收剂,具有良好的CO_(2)捕集性能,能够有效避免传统吸收剂能耗高、降解快、腐蚀设备和成本高等问题,但其距离实际应用仍需进一步研究与验证。本综述可为CO_(2)捕集胺基吸收剂的种类选择和性能提升提供参考。 展开更多
关键词 CO_(2)捕集 胺基吸收剂 化学吸收法 吸收性能 再生能耗
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An improved and robust method of estimating ice sheet elevation changes with ICESat-2 altimetry data
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作者 Benxin Zhu Shengkai Zhang +3 位作者 Feng Xiao Xiao Li Tingguo Lu Xing Yuan 《Geodesy and Geodynamics》 2025年第6期717-726,共10页
Elevation change monitoring of the Antarctic ice sheet has been a key issue in global change research.Satellite altimetry has been proven to be effective in detecting ice sheet variations. With the development of ICES... Elevation change monitoring of the Antarctic ice sheet has been a key issue in global change research.Satellite altimetry has been proven to be effective in detecting ice sheet variations. With the development of ICESat-2, many elevation observations can be used to derive elevation changes. However, the large amount of multitemporal data may include anomalous data points, increasing the uncertainty of the results. In this work, we improved the traditional repeat track method by introducing the Institute of Geodesy and Geophysics Ⅲ(IGGⅢ) method to obtain high-accuracy estimates of elevation change. The improved method was applied to analyze elevation changes along the transect from Zhongshan Station to Dome A in East Antarctica via ICESat-2 satellite altimetry data. The results show that the improved and traditional methods yield consistent numerical and spatial elevation change distributions. The elevation change calculated via the traditional method is 0.033 ± 0.131 m/yr, whereas the elevation change estimated via the IGGⅢ robust estimation method is 0.033 ± 0.109 m/yr from March 2019 to December 2021.In terms of spatial distribution, elevation changes in inland areas remain close to equilibrium, whereas regions with steeper ice sheet margins exhibit positive accumulation trends in elevation changes. The improved method reduces the standard error of the adjustment function from 0.975 to 0.691 m/yr. The improvement is particularly remarkable in the area between 72°S and 77°S. The results demonstrate that the IGGⅢ method effectively reduces errors caused by the inclusion of anomalous data and maintains the high data utilization rate of repeat-orbit methods. 展开更多
关键词 Satellite altimetry Repeat tracks method Ice sheet elevation change Robust estimation ICESat-2
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Simulation of CO_(2)-water two-phase fluid displacement characteristics based on the phase field method
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作者 Changnu Zeng Yiyang Zhang +1 位作者 Hu Lu Zhao Lu 《Deep Underground Science and Engineering》 2025年第4期725-738,共14页
The two-phase flow in porous media is affected by multiple factors.In the present study,a two-dimensional numerical model of porous media was developed using the actual pore structure of the core sample.The phase fiel... The two-phase flow in porous media is affected by multiple factors.In the present study,a two-dimensional numerical model of porous media was developed using the actual pore structure of the core sample.The phase field method was utilized to simulate the impact of displacement velocity,the water-gas viscosity ratio,and the density ratio on the flow behavior of two-phase fluids in porous media.The effectiveness of displacement was evaluated by analyzing CO_(2)saturation levels.The results indicate that the saturation of CO_(2)in porous media increased as the displacement velocity increased.When the displacement velocity exceeded 0.01 m/s,there was a corresponding increase in CO_(2)saturation.Conversely,when the displacement velocity was below this threshold,the impact on CO_(2)saturation was minimal.An“inflection point,”M3,was present in the viscosity ratio.When the viscosity of CO_(2)is less than 8.937×10^(-5)Pa·s(viscosity ratio below M3),variations in the viscosity of CO_(2)had little impact on its saturation.Conversely,when the viscosity of CO_(2)exceeded 8.937×10^(-5)Pa·s(viscosity ratio greater than M3),saturation increased with an increase in the viscosity ratio.In terms of the density ratio,the saturation of CO_(2)increased monotonically with an increase in the density ratio.Similarly,increasing density ratios resulted in a monotonic increase in CO_(2)saturation,though this trend was less pronounced in numerical simulations.Analysis results of displacement within dead-end pores using pressure and velocity diagrams reveal eddy currents as contributing factors.Finally,the impact of pore throat structure on the formation of dominant channels was examined. 展开更多
关键词 CO_(2)geological storage displacement efficiency enhancement phase field method real core two-phase flow
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TCMLCM:an intelligent question-answering model for traditional Chinese medicine lung cancer based on the KG2TRAG method
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作者 Chunfang ZHOU Qingyue GONG +2 位作者 Wendong ZHAN Jinyang ZHU Huidan LUAN 《Digital Chinese Medicine》 2025年第1期36-45,共10页
Objective To improve the accuracy and professionalism of question-answering(QA)model in traditional Chinese medicine(TCM)lung cancer by integrating large language models with structured knowledge graphs using the know... Objective To improve the accuracy and professionalism of question-answering(QA)model in traditional Chinese medicine(TCM)lung cancer by integrating large language models with structured knowledge graphs using the knowledge graph(KG)to text-enhanced retrievalaugmented generation(KG2TRAG)method.Methods The TCM lung cancer model(TCMLCM)was constructed by fine-tuning Chat-GLM2-6B on the specialized datasets Tianchi TCM,HuangDi,and ShenNong-TCM-Dataset,as well as a TCM lung cancer KG.The KG2TRAG method was applied to enhance the knowledge retrieval,which can convert KG triples into natural language text via ChatGPT-aided linearization,leveraging large language models(LLMs)for context-aware reasoning.For a comprehensive comparison,MedicalGPT,HuatuoGPT,and BenTsao were selected as the baseline models.Performance was evaluated using bilingual evaluation understudy(BLEU),recall-oriented understudy for gisting evaluation(ROUGE),accuracy,and the domain-specific TCM-LCEval metrics,with validation from TCM oncology experts assessing answer accuracy,professionalism,and usability.Results The TCMLCM model achieved the optimal performance across all metrics,including a BLEU score of 32.15%,ROUGE-L of 59.08%,and an accuracy rate of 79.68%.Notably,in the TCM-LCEval assessment specific to the field of TCM,its performance was 3%−12%higher than that of the baseline model.Expert evaluations highlighted superior performance in accuracy and professionalism.Conclusion TCMLCM can provide an innovative solution for TCM lung cancer QA,demonstrating the feasibility of integrating structured KGs with LLMs.This work advances intelligent TCM healthcare tools and lays a foundation for future AI-driven applications in traditional medicine. 展开更多
关键词 Traditional Chinese medicine(TCM) Lung cancer Question-answering Large language model Fine-tuning Knowledge graph KG2TRAG method
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Cu/SiO_(2)催化剂的制备及其乙醇脱氢制乙醛性能
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作者 魏浩宇 李晓晨 +4 位作者 苏振宇 王春雪 宋诗鹏 王国玮 祝晓琳 《石化技术与应用》 2026年第1期8-12,19,共6页
分别采用NH_(3)蒸发法和浸渍法制备了一系列Cu/SiO_(2)催化剂,利用X射线粉末衍射仪、全自动多用吸附仪、物理吸附仪、透射电子显微镜等仪器对上述催化剂进行了表征,考察了催化剂制备参数和反应条件对乙醇脱氢反应性能的影响。结果表明:... 分别采用NH_(3)蒸发法和浸渍法制备了一系列Cu/SiO_(2)催化剂,利用X射线粉末衍射仪、全自动多用吸附仪、物理吸附仪、透射电子显微镜等仪器对上述催化剂进行了表征,考察了催化剂制备参数和反应条件对乙醇脱氢反应性能的影响。结果表明:相比浸渍法,NH_(3)蒸发法制备的催化剂的活性组分金属Cu分散得更均匀,在乙醇脱氢反应中呈现出更高的催化活性;NH_(3)蒸发法制备的催化剂在Cu负载量(质量分数)为5%,反应温度为320℃,进料质量空速为2 h-1的优化条件下,乙醇转化率约为85.0%,乙醛选择性高于95.0%,且在60 h内呈现出良好的反应稳定性。 展开更多
关键词 Cu/SiO_(2)催化剂 制备方法 NH_(3)蒸发法 金属负载量 乙醇脱氢 乙醛 稳定性 选择性
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临床药师主导的T2DM患者全周期管理模式构建
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作者 蒋媛媛 郑桂梅 +2 位作者 曹耀华 谢泽宇 曹伟灵 《中国药房》 北大核心 2026年第1期92-98,共7页
目的构建临床药师主导的2型糖尿病(T2DM)患者全周期管理模式。方法基于文献分析,初步构建临床药师主导的T2DM患者全周期管理模式的基本框架与条目;采用德尔菲法向26名专家进行函询,确定该模式的具体实施条目;运用层次分析(AHP)法确定各... 目的构建临床药师主导的2型糖尿病(T2DM)患者全周期管理模式。方法基于文献分析,初步构建临床药师主导的T2DM患者全周期管理模式的基本框架与条目;采用德尔菲法向26名专家进行函询,确定该模式的具体实施条目;运用层次分析(AHP)法确定各级条目的权重,并对模式条目进行信效度分析。结果两轮专家函询的问卷回收率分别为86.67%、100%,专家权威系数为0.88;三级条目的肯德尔协调系数分别为0.064、0.084(χ^(2)检验的P值均小于0.05);AHP模型各层级判断矩阵的一致性比率均小于0.1。所建临床药师主导的T2DM患者全周期管理模式包含3个一级条目(T2DM患者住院期间的药学服务路径、T2DM住院患者的低血糖药学管理路径、T2DM出院患者的药学随访路径,权重分别为0.098、0.568、0.334)、12个二级条目(住院1~2 d的药学服务、入院评估及宣教等,权重为0.143~0.333)和37个三级条目(依从性评估、核查出院带药方案等,权重为0.068~0.750)。该模式上述一级条目及总体的Cronbach’s α系数分别为0.762、0.879、0.928、0.951,条目水平、量表水平的内容效度指数分别为0.967、0.808。结论成功构建了临床药师主导的T2DM患者全周期管理模式,该模式具有较高的科学性与可靠性。 展开更多
关键词 临床药师 2型糖尿病 全周期管理模式 德尔菲法 层次分析法
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熔盐法制备桦木基二维多孔碳材料及其CO_(2)吸附性能研究
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作者 马霄彤 刘小好 马培勇 《广州化工》 2026年第1期57-60,共4页
以桦木木屑作为碳前体,采用KCl作为添加剂,制备二维多孔碳材料,并将其应用于CO_(2)吸附。探讨了热解温度以及KCl和桦木木屑的比例对于多孔碳结构的影响,并初步探究了其作为CO_(2)吸附剂的吸附性能。研究结果表明:热解温度以及KCl和桦木... 以桦木木屑作为碳前体,采用KCl作为添加剂,制备二维多孔碳材料,并将其应用于CO_(2)吸附。探讨了热解温度以及KCl和桦木木屑的比例对于多孔碳结构的影响,并初步探究了其作为CO_(2)吸附剂的吸附性能。研究结果表明:热解温度以及KCl和桦木木屑的比例均对多孔碳材料的微观形貌和孔隙结构具有显著影响。在0℃的1 bar的压力下,KAC-4:1-800表现出较高的CO_(2)吸附量(3.469 mmol/g),这可能与其超薄的二维结构(约4.5 nm)和高比表面积(965.8 m2/g)有关。 展开更多
关键词 熔盐法 生物质 多孔碳材料 CO_(2)吸附
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基于营卫理论运用引卫入阴法论治2型糖尿病合并失眠的个案报告
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作者 王祎 李敬林 《中国现代药物应用》 2026年第3期139-142,共4页
2型糖尿病(T2DM)合并失眠的中医病名归纳为“消渴不寐”,目前临床治疗多采取控制血糖配合辅助睡眠的药物,但此类治疗方法会引起药物依赖并伴随一定的不良反应。中医理论与现代医学研究,认为2型糖尿病合并失眠属于“卫气不得入阴”,其发... 2型糖尿病(T2DM)合并失眠的中医病名归纳为“消渴不寐”,目前临床治疗多采取控制血糖配合辅助睡眠的药物,但此类治疗方法会引起药物依赖并伴随一定的不良反应。中医理论与现代医学研究,认为2型糖尿病合并失眠属于“卫气不得入阴”,其发生发展主要责之于脾胃、肝、心、肾,肝气郁结、脾胃失和、扰乱心神、心肾不交进一步影响营卫的生成与运行,营卫不能调和则影响人体寤寐、血糖波动。针对疾病发生发展的病因病机提出了“引卫入阴法”治疗2型糖尿病合并失眠。引卫入阴法为治疗2型糖尿病伴失眠提供新思路,本文将报告1例68岁2型糖尿病合并失眠患者经该方法治疗取得的理想效果。 展开更多
关键词 2型糖尿病 失眠 营卫理论 引卫入阴法
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Integrated process of large-scale and size-controlled SnO_2 nanoparticles by hydrothermal method 被引量:3
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作者 曹雪 舒永春 +2 位作者 胡永能 李广平 刘畅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期725-730,共6页
SnO2 nanoparticles with the average particle size of 5-30 nm were synthesized using SnCl4·5H2O as the precursor and NH3·H2O as the mineralizing agent by hydrothermal method.In the case of 1 kg/batch producti... SnO2 nanoparticles with the average particle size of 5-30 nm were synthesized using SnCl4·5H2O as the precursor and NH3·H2O as the mineralizing agent by hydrothermal method.In the case of 1 kg/batch production,the effects of synthesis conditions including solution concentration,reaction temperature,pressure,time and pH value on the grain size,particle morphology and crystal structure of SnO2 were systematically studied.The particles were characterized by X-ray diffraction(XRD) and transmission electron microscopy(TEM).The results show that,the particle size can be well controlled in the range of 5-30 nm by adjusting the processing parameters such as reaction temperature and time when the crystal structure and particle morphology remain unchanged.The previous reports,the unusual dependences of the grain size of SnO2 on reaction temperature and time were found.The mechanism for such abnormal grain growth behavior was tentatively elucidated. 展开更多
关键词 SNO2 NANOPARTICLES hydrothermal method
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Preparation and Characterization of Nanometer TiO_2 by Hydrolysis Precipitation Method 被引量:1
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作者 方世杰 徐明霞 +1 位作者 郝俊杰 汪成建 《Transactions of Tianjin University》 EI CAS 2002年第2期79-82,共4页
Nanometer TiO 2 powders were obtained from TiOSO 4 and studied by XRD, TEM and BET. The result indicated that pH and heat treatment temperature have great effects on their grain size and crystal phase structu... Nanometer TiO 2 powders were obtained from TiOSO 4 and studied by XRD, TEM and BET. The result indicated that pH and heat treatment temperature have great effects on their grain size and crystal phase structure. Annealed at 500 ℃, nanometer TiO 2 with a specific surface area of 101.39 m 2 ·g -1 and a grain size about 10 nm were obtained(pH=5); and with a specific surface area of 95.48 m 2 ·g -1 and a grain size about 30 nm were obtained(pH=10). The research indicated that crystal phase transformation of rutile at 750 ℃made great promotion in grain size growth. 展开更多
关键词 nanometer Tio 2 hydrolysis precipitation method PH crystal phase transformation
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Synthesis of nanostructured Li_2FeSiO_4/C cathode for lithium-ion battery by solution method 被引量:1
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作者 杨蓉 刘晓艳 +2 位作者 曲冶 雷京 Jou-Hyeon AHN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2529-2534,共6页
Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization... Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization. The amount of carbon in the composite is less than 10% (mass fraction), and the X-ray diffraction result confirms that the sample is of pure single phase indexed with the orthorhombic Pmn21 space group. The particle size of the Li2FeSiO4/C synthesized at 700 °C for 9 h is very fine and spherical-like with a size of 200 nm. The electrochemical performance of this material, including reversible capacity, cycle number, and charge-discharge characteristics, were tested. The cell of this sample can deliver a discharge capacity of 166 mA-h/g at C/20 rate in the first three cycles. After 30 cycles, the capacity decreases to 158 mA-h/g, and the capacity retention is up to 95%. The results show that this method can prepare nanosphere-like Li2FeSiO4/C composite with good electrochemical performance. 展开更多
关键词 lithium-ion batteries cathode material Li2FeSiO4/C solution method
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What is the Most Effective Method of Error Correction in L2 Writing? 被引量:2
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作者 顾红兵 《海外英语》 2011年第10X期37-39,共3页
The efficacy of error correction and various kinds of correction approaches is one of the key issues in second language writing faced by both teachers and researchers. The current paper reviews the definition of error... The efficacy of error correction and various kinds of correction approaches is one of the key issues in second language writing faced by both teachers and researchers. The current paper reviews the definition of error correction and examines the different views on whether error correction in L2 writing should be corrected. In particular, the paper discusses and analyses the three common correction methods: direct correction, peer feedback and indirect correction. Teachers are encouraged to weigh and analyze the advantages and disadvantages of these methods according to the current literature, employ the most beneficial error correction method in L2 writing, and adapt its suitability to their teaching context. 展开更多
关键词 ERROR CORRECTION L2 WRITING effective method
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Hydrogen storage properties of Mg-TiO_2 composite powder prepared by arc plasma method 被引量:5
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作者 潘银成 邹建新 +1 位作者 曾小勤 丁文江 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3834-3839,共6页
Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg+5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase component... Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg+5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase components and microstructure of the composite powder. The hydrogen sorption properties of the composite powder were investigated by DSC and PCT techniques. According to the data from PCT measurements, the hydrogenation enthalpy and entropy changes of the composite powder are calculated to be-71.5 kJ/mol and-130.1 J/(K·mol), respectively. Besides, the hydrogenation activation energy is determined to be 77.2 kJ/ mol. The results indicate that TiO2 added into Mg by arc plasma method can act as a catalyst to improve the hydrogen sorption kinetic properties of Mg. 展开更多
关键词 nanostructured composite Mg TIO2 hydrogen storage arc plasma method
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MnO_(2)纳米复合材料吸附处理工业废水的应用研究进展 被引量:1
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作者 王坤 孙海翔 +4 位作者 唐玉朝 黄显怀 张北平 伍昌年 陈伟 《应用化工》 北大核心 2025年第7期1861-1866,1874,共7页
二氧化锰(MnO_(2))作为一种重要的过渡金属氧化物,因其丰富的储量、多样的晶型以及出色的性能而备受瞩目。当MnO_(2)被纳米化处理后,其颗粒尺寸显著减小,比表面积显著增大,进而实现了材料性能的优化,大大拓宽了其应用领域。总结了MnO_(2... 二氧化锰(MnO_(2))作为一种重要的过渡金属氧化物,因其丰富的储量、多样的晶型以及出色的性能而备受瞩目。当MnO_(2)被纳米化处理后,其颗粒尺寸显著减小,比表面积显著增大,进而实现了材料性能的优化,大大拓宽了其应用领域。总结了MnO_(2)纳米复合材料作为吸附剂在工业废水污染物处理中的应用研究进展。通过介绍MnO_(2)纳米复合材料形貌特征及其对重金属、有机污染物和无机污染物的吸附效果,阐述MnO_(2)纳米复合材料吸附剂在处理不同污染物的吸附机理,并展望MnO_(2)纳米复合材料的发展方向。 展开更多
关键词 二氧化锰(MnO_(2)) 吸附机理 制备方法 工业废水
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Preparation and Characterization of Nanometer TiO2 by Hydrolysis Precipitation Method 被引量:1
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作者 方世杰 徐明霞 +1 位作者 郝俊杰 汪成建 《Transactions of Tianjin University》 EI CAS 2002年第2期79-82,共页
Nanometer TiO 2 powders were obtained from TiOSO 4 and studied by XRD, TEM and BET. The result indicated that pH and heat treatment temperature have great effects on their grain size and crystal phase structu... Nanometer TiO 2 powders were obtained from TiOSO 4 and studied by XRD, TEM and BET. The result indicated that pH and heat treatment temperature have great effects on their grain size and crystal phase structure. Annealed at 500 ℃, nanometer TiO 2 with a specific surface area of 101.39 m 2 ·g -1 and a grain size about 10 nm were obtained(pH=5); and with a specific surface area of 95.48 m 2 ·g -1 and a grain size about 30 nm were obtained(pH=10). The research indicated that crystal phase transformation of rutile at 750 ℃made great promotion in grain size growth. 展开更多
关键词 nanometer Tio 2 hydrolysis precipitation method PH crystal phase transformation
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BSL-2实验室人员生物安全能力评价指标体系研究 被引量:2
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作者 刘志勇 钱子煜 +3 位作者 龚睿婕 李梦 陶艳琳 戴潇瀚 《健康发展与政策研究》 北大核心 2025年第1期104-110,共7页
目的建立BSL-2实验室不同类型工作人员防范和应对生物安全风险能力评价的指标体系。方法根据国内相关法律法规、标准和相关文献,建立指标库,遴选全国20位病原微生物检测专家,通过德尔菲法和层次分析法相结合的方式确定各个指标和权重。... 目的建立BSL-2实验室不同类型工作人员防范和应对生物安全风险能力评价的指标体系。方法根据国内相关法律法规、标准和相关文献,建立指标库,遴选全国20位病原微生物检测专家,通过德尔菲法和层次分析法相结合的方式确定各个指标和权重。结果经过两轮专家询函,针对管理人员、实验人员和辅助人员3类人员,建立了包含4个一级指标、18个二级指标和73个三级指标的评价体系。4个一级指标包括“危害因素的识别能力”“风险的控制能力”“管理能力及执行力”“应急能力”。两轮咨询的专家积极系数分别为95.24%和100.00%,权威系数为0.945,专家意见协调程度具有一致性。结论本研究建立的评价指标体系能够全面、准确且科学地评价实验室不同类型工作人员在生物安全方面的工作能力,根据评估结果进行必要的调整和改善,可提升BSL-2实验室人员的生物安全能力,增强实验室整体的生物安全水平。 展开更多
关键词 BSL-2实验室 生物安全能力评价 德尔菲法 层次分析法
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BiOCl/Bi_(2)O_(2)CO_(3)复合光催化剂的制备及其光催化性能研究
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作者 王艳 王换换 +2 位作者 刘慧 马文萱 王国永 《现代化工》 北大核心 2025年第6期125-130,共6页
以BiCl_(3)为原料,通过调控Na_(2)CO_(3)用量制备不同的光催化剂,并利用XRD、FT-IR、UV-DRS、XPS、PL等表征手段对其进行表征。结果表明,利用水解法成功合成了BiOCl、Bi_(2)O_(2)CO_(3)和BiOCl/Bi_(2)O_(2)CO_(3)光催化剂,三者均为宽带... 以BiCl_(3)为原料,通过调控Na_(2)CO_(3)用量制备不同的光催化剂,并利用XRD、FT-IR、UV-DRS、XPS、PL等表征手段对其进行表征。结果表明,利用水解法成功合成了BiOCl、Bi_(2)O_(2)CO_(3)和BiOCl/Bi_(2)O_(2)CO_(3)光催化剂,三者均为宽带隙半导体,在可见光下对有色染料有去除效果,主要归功于敏化作用。得益于催化和敏化的联合作用,这些催化剂在全光作用下呈现出较高的去除率,其中BiOCl/Bi_(2)O_(2)CO_(3)催化剂性能最佳。同时,还对其光敏化和光催化的机理进行了研究。 展开更多
关键词 光催化 BiOCl BiOCl/Bi_(2)O_(2)CO_(3) Bi_(2)O_(2)CO_(3) 异质结 水解法
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