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Efficient removal of Al(Ⅲ)and P507 from high concentration MgCl_(2)solution based on in-situ reaction strategy
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作者 Qiang WANG Meng WANG +3 位作者 Zong-yu FENG Yong-qi ZHANG Xiao-wei HUANG Xiang-xin XUE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期3042-3053,共12页
For a highly efficient recycling of a wastewater containing a high concentration of MgCl_(2),Al(Ⅲ)and P507 were scheduled to be removed in advance.In this study,the in-situ removal of Al(Ⅲ)and P507 from a high conce... For a highly efficient recycling of a wastewater containing a high concentration of MgCl_(2),Al(Ⅲ)and P507 were scheduled to be removed in advance.In this study,the in-situ removal of Al(Ⅲ)and P507 from a high concentration MgCl_(2)solution at different pH values and Al/P molar ratios was investigated.The results showed that P507 formed organic complexes of Al_(x)(OH)_y^(Z+)-P507 at pH of 2.0-4.0.At pH of 4.0-5.0,Al(Ⅲ)precipitated and transferred into Al(OH)_(3)with a flocculent amorphous morphology.Active sites on the Al(OH)_(3)surface enhanced the removal efficiency of P507.At pH of 6.0-6.5,Al(Ⅲ)and Mg(Ⅱ)formed layered crystalline Al(OH)_(3)and MgAl_(2)(OH)_(8with)small pore channels and fewer active sites,resulting in a reduced removal efficiency of P507.When the Al/P molar ratio exceeded 13 and the pH was between 4.0 and 5.0,the removal rates of both Al(Ⅲ)and P507 were higher than98%,while the concentration loss of Mg(Ⅱ)was only 0.2%-0.9%. 展开更多
关键词 in-situ removal AL(III) P507 MgCl_(2)solution pH Al/P molar ratio
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Improved combustion stability of biogas at different CO_(2) concentrations using inhomogeneous partially premixed stratified flames
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作者 Mohy Saad Mansour Maged Kiriakos +1 位作者 Lili Hao Mohamed Amr Serag-Eldin 《Global Energy Interconnection》 EI CSCD 2024年第4期486-502,共17页
Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only real... Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas field.To improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this study.The thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame structure.The flame size was reduced by increasing the CO_(2) concentration and the flames became lighter blue.The flame temperature also decreased with increase in CO_(2) concentration.Flame stability was reduced by increasing the CO_(2) concentration.However,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the stability.Accordingly,the IPPS mode of combustion should be suitable for the combustion and stabilization of biogas.This should support the design of highly stabilized biogas turbulent flames independent of CO_(2) concentration.The data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant. 展开更多
关键词 BIOGAS Renewable energy Effect of CO_(2) Combustion stability Burner design Renewable fuels Partial premixed
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Neutrophil-to-lymphocyte ratio associated with renal function in type 2 diabetic patients
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作者 Jin-Li Gao Jue Shen +5 位作者 Li-Ping Yang Li Liu Kai Zhao Xiao-Rong Pan Lei Li Ji-Ji Xu 《World Journal of Clinical Cases》 SCIE 2024年第14期2308-2315,共8页
BACKGROUND Type 2 diabetes mellitus(T2DM)is a leading risk factor for the development and progression of chronic kidney disease(CKD).However,an accurate and con-venient marker for early detection and appropriate manag... BACKGROUND Type 2 diabetes mellitus(T2DM)is a leading risk factor for the development and progression of chronic kidney disease(CKD).However,an accurate and con-venient marker for early detection and appropriate management of CKD in in-dividuals with T2DM is limited.Recent studies have demonstrated a strong correlation between the neutrophil-to-lymphocyte ratio(NLR)and CKD.None-theless,the predictive value of NLR for renal damage in type 2 diabetic patients remains understudied.This study included 1040 adults aged 65 or older with T2DM from Shanghai's Community Health Service Center.The total number of neutrophils and lym-phocytes was detected,and NLR levels were calculated.CKD was defined as an estimated glomerular filtration rate≤60 mL/min/1.73 m².Participants were di-vided into four groups based on NLR levels.The clinical data and biochemical characteristics were compared among groups.A multivariate logistic regression model was used to analyze the association between NLR levels and CKD.RESULTS Significant differences were found in terms of sex,serum creatinine,blood urea nitrogen,total cholesterol,and low-density lipoprotein cholesterol among patients with T2DM in different NLR groups(P<0.0007).T2DM patients in the highest NLR quartile had a higher prevalence of CKD(P for trend=0.0011).Multivariate logistic regression analysis indicated that a high NLR was an independent risk factor for CKD in T2DM patients even after adjustment for important clinical and pathological parameters(P=0.0001,odds ratio=1.41,95%confidence intervals:1.18-1.68).CONCLUSION An elevated NLR in patients with T2DM is associated with higher prevalence of CKD,suggesting that it could be a marker for the detection and evaluation of diabetic kidney disease. 展开更多
关键词 Type 2 diabetes mellitus Neutrophil-to-lymphocyte ratio Chronic kidney disease Logistic regression Diabetes mellitus
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Inhibiting Voltage Decay in Li-Rich Layered Oxide Cathode:From O3-Type to O2-Type Structural Design
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作者 Guohua Zhang Xiaohui Wen +2 位作者 Yuheng Gao Renyuan Zhang Yunhui Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期81-102,共22页
Li-rich layered oxide(LRLO)cathodes have been regarded as promising candidates for next-generation Li-ion batteries due to their exceptionally high energy density,which combines cationic and anionic redox activities.H... Li-rich layered oxide(LRLO)cathodes have been regarded as promising candidates for next-generation Li-ion batteries due to their exceptionally high energy density,which combines cationic and anionic redox activities.However,continuous voltage decay during cycling remains the primary obstacle for practical applications,which has yet to be fundamentally addressed.It is widely acknowledged that voltage decay originates from the irreversible migration of transition metal ions,which usually further exacerbates structural evolution and aggravates the irreversible oxygen redox reactions.Recently,constructing O2-type structure has been considered one of the most promising approaches for inhibiting voltage decay.In this review,the relationship between voltage decay and structural evolution is systematically elucidated.Strategies to suppress voltage decay are systematically summarized.Additionally,the design of O2-type structure and the corresponding mechanism of suppressing voltage decay are comprehensively discussed.Unfortunately,the reported O2-type LRLO cathodes still exhibit partially disordered structure with extended cycles.Herein,the factors that may cause the irreversible transition metal migrations in O2-type LRLO materials are also explored,while the perspectives and challenges for designing high-performance O2-type LRLO cathodes without voltage decay are proposed. 展开更多
关键词 Lithium-ion batteries Li-rich layered oxide Voltage decay Migration of transition metal ions O2-type structural design
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外周血TLR2、TIPE2、NLR联合检测对机械通气新生儿呼吸机相关性肺炎的预测价值
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作者 曲海新 郭卫平 +2 位作者 袁二伟 历奇 刘璐 《检验医学与临床》 CAS 2024年第20期2985-2989,共5页
目的探讨外周血Toll样受体2(TLR2)、肿瘤坏死因子α诱导蛋白8样因子2(TIPE2)、中性粒细胞与淋巴细胞比值(NLR)联合检测对机械通气新生儿呼吸机相关性肺炎(VAP)的预测价值。方法选取2020年6月至2023年6月河北北方学院附属第一医院进行机... 目的探讨外周血Toll样受体2(TLR2)、肿瘤坏死因子α诱导蛋白8样因子2(TIPE2)、中性粒细胞与淋巴细胞比值(NLR)联合检测对机械通气新生儿呼吸机相关性肺炎(VAP)的预测价值。方法选取2020年6月至2023年6月河北北方学院附属第一医院进行机械通气治疗的232例新生儿作为研究对象。将发生VAP的新生儿纳入VAP组,其余纳入非VAP组。检测并比较两组外周血TLR2、TIPE2表达水平和NLR。绘制受试者工作特征(ROC)曲线评估外周血TLR2、TIPE2、NLR单独及联合预测机械通气新生儿VAP发生的价值。采用多因素Logistic回归分析机械通气新生儿发生VAP的影响因素。结果232例机械通气新生儿中,60例发生VAP,发生率为25.86%,纳入VAP组;其余172例未发生VAP,纳入非VAP组。VAP组和非VAP组机械通气时间、置管次数和吸痰次数比较,差异均有统计学意义(P<0.05)。VAP组TLR2相对表达水平和NLR高于非VAP组,TIPE2相对表达水平低于非VAP组,差异均有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,机械通气时间≥3 d、置管次数≥2次、吸痰次数≥5次/天、TLR2相对表达水平升高、NLR升高是械通气新生儿发生VAP的危险因素(P<0.05),TIPE2相对表达水平升高是新生儿发生VAP的保护因素(P<0.05)。ROC曲线分析结果显示,TLR2、TIPE2和NLR单独预测机械通气新生儿发生VAP的曲线下面积(AUC)分别为0.783、0.754、0.745;且外周血TLR2、TIPE2、NLR联合检测预测机械通气新生儿发生VAP的AUC为0.823。结论外周血TLR2、TIPE2和NLR均是机械通气新生儿发生VAP的独立影响因素,且联合检测有助于预测VAP的发生。 展开更多
关键词 机械通气 新生儿 呼吸机相关性肺炎 TOLL样受体2 肿瘤坏死因子α诱导蛋白8样因子2 中性粒细胞与淋巴细胞比值
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2型糖尿病患者血清25-羟维生素D水平与代谢指标的相关性
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作者 侯小丽 吴述光 +4 位作者 潘静 李健 邹慧 曹在新 张秀英 《新乡医学院学报》 CAS 2024年第11期1043-1047,1054,共6页
目的分析2型糖尿病患者25-羟维生素D[25(OH)D]水平,初步了解血清25(OH)D水平与2型糖尿病患者糖化血红蛋白(HbA1c)、胰岛功能等代谢指标的相关性。方法选择新乡市第一人民医院内分泌科2020年1月至2020年12月收治的459例2型糖尿病患者为... 目的分析2型糖尿病患者25-羟维生素D[25(OH)D]水平,初步了解血清25(OH)D水平与2型糖尿病患者糖化血红蛋白(HbA1c)、胰岛功能等代谢指标的相关性。方法选择新乡市第一人民医院内分泌科2020年1月至2020年12月收治的459例2型糖尿病患者为研究对象。收集患者的临床资料,包括性别、年龄、血清25(OH)D、空腹胰岛素、C肽、HbA1c、空腹血糖、餐后血糖、尿微量白蛋白、尿白蛋白肌酐比值、血钙、血尿酸(UA)、三酰甘油(TG)、总胆固醇(TCH)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)等。根据血清25(OH)D水平将患者分为充足组[n=20,25(OH)D≥30μg·L^(-1)]、不足组[n=95,20μg·L^(-1)≤25(OH)D<30μg·L^(-1)]、缺乏组[n=231,10μg·L^(-1)≤25(OH)D<20μg·L^(-1)]、严重缺乏组[n=113,25(OH)D<10μg·L^(-1)]。比较4组患者各代谢指标的差异,采用Pearson相关分析25(OH)D与各代谢指标的相关性。结果2型糖尿病患者血清25(OH)D水平为3.00~46.59(15.75±0.35)μg·L^(-1),男性患者的血清25(OH)D水平显著高于女性患者(P<0.05)。2型糖尿病患者25(OH)D缺乏的患病率为74.9%(344/459),25(OH)D缺乏主要发生在1、2、3、4、11、12月份。不足组、缺乏组和严重缺乏组患者HbA1c显著高于充足组(P<0.05),缺乏组和严重缺乏组患者HbA1c显著高于不足组(P<0.05);缺乏组和严重缺乏组患者HbA1c比较差异无统计学意义(P>0.05)。充足组与不足组、缺乏组与严重缺乏组患者空腹血糖比较差异无统计学意义(P>0.05);缺乏组和严重缺乏组患者空腹血糖显著高于充足组、不足组(P<0.05)。充足组、不足组、缺乏组患者空腹胰岛素、尿微量白蛋白、日尿白蛋白总量、尿白蛋白肌酐比值比较差异无统计学意义(P>0.05);严重缺乏组患者空腹胰岛素显著低于充足组、不足组和缺乏组,尿微量白蛋白、日尿白蛋白总量、尿白蛋白肌酐比值显著高于充足组、不足组和缺乏组(P<0.05)。4组患者的稳态模型评估的胰岛素抵抗指数(HOMA-IR)、血清白蛋白、血肌酐、餐后1 h血糖、餐后2 h血糖、餐后3 h血糖、空腹C肽、餐后1 h C肽、餐后2 h C肽、餐后3 h C肽、TG、TCH、LDL、HDL、血UA、血钙比较差异均无统计学意义(P>0.05)。Pearson相关性分析结果显示,2型糖尿病患者血清25(OH)D水平与HbA1c、尿微量白蛋白、尿白蛋白肌酐比值呈负相关(r=-0.093、-0.166、-0.157,P<0.05),与空腹胰岛素呈正相关(r=0.089,P<0.05)。2型糖尿病患者血清25(OH)D水平与空腹血糖、HOMA-IR、血清白蛋白、血肌酐、餐后1 h血糖、餐后2 h血糖、餐后3 h血糖、空腹C肽、餐后1 h C肽、餐后2 h C肽、餐后3 h C肽、TG、TCH、LDL、HDL、血UA、血钙等无相关性(P>0.05)。结论2型糖尿病患者25(OH)D缺乏与不足普遍存在,女性患者缺乏更明显。2型糖尿病患者25(OH)D水平与空腹胰岛素呈正相关,与HbA1c、尿微量白蛋白、尿白蛋白肌酐比值呈负相关,25(OH)D缺乏的2型糖尿病患者主要分布在1、2、3、4、11、12月份。 展开更多
关键词 2型糖尿病 25-羟维生素D 胰岛素 C肽 糖化血红蛋白 尿微量白蛋白 尿白蛋白肌酐比值
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Nb_(2)O_(5)对3Y-TZP陶瓷性能影响的研究
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作者 林信平 李和祯 陈戈 《中国锰业》 2024年第2期47-49,61,共4页
研究了Nb_(2)O_(5)的加入对3Y-TZP陶瓷性能的影响,主要包括对硬度、韧性、冲击性的影响,并且结合显微形貌以及XRD物相图谱分析出的晶轴比进行分析。结果表明,随着Nb_(2)O_(5)添加量的增加,陶瓷的韧性呈现提升趋势,硬度呈现降低趋势,强... 研究了Nb_(2)O_(5)的加入对3Y-TZP陶瓷性能的影响,主要包括对硬度、韧性、冲击性的影响,并且结合显微形貌以及XRD物相图谱分析出的晶轴比进行分析。结果表明,随着Nb_(2)O_(5)添加量的增加,陶瓷的韧性呈现提升趋势,硬度呈现降低趋势,强度呈现先上升后下降趋势。这一现象的产生,一方面归因于Nb_(2)O_(5)的加入让陶瓷生成异相小晶粒,进而提供异相颗粒增韧阻碍裂纹扩展;另一方面,由于Nb^(5+)的引入提高了晶轴比,从而让相变更容易发生。综上所述,Nb_(2)O_(5)的最佳添加质量分数为0.5%。 展开更多
关键词 3Y-TZP Nb_(2)O_(5) 异相颗粒增韧 晶轴比
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高速S-CO_(2)向心透平几何参数优化及变工况特性分析
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作者 孙玉伟 陈晨 +2 位作者 秦天阳 袁成清 赵庆 《中国电机工程学报》 EI CSCD 北大核心 2024年第6期2319-2329,I0020,共12页
透平是热力循环中实现热功转换的核心设备,优化透平几何参数以改善气动性能,是提升系统热效率的关键。该文以面向某船舶主机烟气余热利用的超临界二氧化碳布雷顿循环透平设计参数为基础,给出向心透平主要几何参数,采用耦合CO_(2)真实物... 透平是热力循环中实现热功转换的核心设备,优化透平几何参数以改善气动性能,是提升系统热效率的关键。该文以面向某船舶主机烟气余热利用的超临界二氧化碳布雷顿循环透平设计参数为基础,给出向心透平主要几何参数,采用耦合CO_(2)真实物性参数的CFX仿真方法,分析几何参数动、静叶包角以及叶轮出口几何角对透平性能的影响规律并进行参数优化,进一步研究非设计工况下的透平运行特性。结果表明:增大静叶包角会使动叶前缘出现扰动涡流并减少余速损失,增大叶轮出口几何角,动叶包角对透平效率的影响规律不变,但效率峰值点会沿动叶包角减小的方向移动;动、静叶包角和叶轮出口几何角分别为49°、21.5°、25°时透平设计点总-静等熵效率高达87.99%,相比优化前,提高0.54个百分点;透平偏离设计点±20%工况下等熵效率大于80%。结果可为超临界二氧化碳高速向心透平设计提供一定参考。 展开更多
关键词 S-CO_(2)向心透平 CFX仿真 气动性能 几何参数优化 变工况
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血清IL-19、VASH-1、NLR在2型糖尿病肾病中的水平及临床意义
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作者 颜建军 李利萍 +5 位作者 胡杨 程木子 程玲 张文静 张楠 张丽莎 《疑难病杂志》 CAS 2024年第9期1090-1093,共4页
目的探讨血清白介素19(IL-19)、血管生成抑制蛋白1(VASH-1)、中性粒细胞与淋巴细胞比值(NLR)在2型糖尿病肾病(T2DN)中的水平及意义。方法选取2020年12月—2022年12月在邯郸市第一医院内分泌一科治疗的T2DN患者100例作为T2DN组,同时收集... 目的探讨血清白介素19(IL-19)、血管生成抑制蛋白1(VASH-1)、中性粒细胞与淋巴细胞比值(NLR)在2型糖尿病肾病(T2DN)中的水平及意义。方法选取2020年12月—2022年12月在邯郸市第一医院内分泌一科治疗的T2DN患者100例作为T2DN组,同时收集单纯2型糖尿病(T2DM)患者100例作为T2DM组,比较2组血清IL-19、VASH-1、NLR水平,并分析血清IL-19、VASH-1、NLR对T2DN的预测价值。结果T2DN组血清IL-19、VASH-1、NLR明显高于T2DM组(t/P=8.374/<0.001、8.277/<0.001、8.762/<0.001)。经二元Logistic回归分析,IL-19、VASH-1、NLR升高是发生T2DN的危险因素[OR(95%CI)=1.120(1.037~1.210)、1.006(1.001~1.012)、2.586(1.165~5.740),P<0.05]。受试者工作特征(ROC)曲线分析显示,IL-19、VASH-1、NLR及三者联合预测T2DN的曲线下面积(AUC)分别为0.807、0.799、0.822、0.854,约登指数分别为0.520、0.490、0.550、0.740,IL-19在最佳截断值对应的敏感度、特异度分别为0.940、0.580,VASH-1为0.660、0.830,NLR为0.920、0.630,三者联合为0.860、0.880。结论T2DN患者血清IL-19、VASH-1、NLR水平升高,且血清IL-19、VASH-1、NLR三者联合对T2DN具有较高的预测价值。 展开更多
关键词 2型糖尿病肾病 白介素19 血管生成抑制蛋白1 中性粒细胞与淋巴细胞比值 诊断价值
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高校BSL-2实验室建设与运行管理
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作者 于川茗 杨亚非 +1 位作者 赵鹏 王满意 《实验室科学》 2024年第5期191-194,199,共5页
近两年越来越多的高校新建、改建BSL-2实验室,目前医疗和疾控系统BSL-2实验室的建设和运行模式与科研属性的高校BSL-2实验室相符性不高、针对性不足,导致高校在建设和改造BSL-2实验室时,可参考的案例和运行管理经验十分有限,缺乏细化指... 近两年越来越多的高校新建、改建BSL-2实验室,目前医疗和疾控系统BSL-2实验室的建设和运行模式与科研属性的高校BSL-2实验室相符性不高、针对性不足,导致高校在建设和改造BSL-2实验室时,可参考的案例和运行管理经验十分有限,缺乏细化指导。针对上述问题,南开大学BSL-2实验室在建筑设计、备案管理、制度文件、日常监管等方面介绍了BSL-2实验室的建设和运行管理经验,供其他高校建设BSL-2实验室借鉴和参考。 展开更多
关键词 BSL-2实验室 建筑设计 备案管理 质量管理 日常监管
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长岭断陷龙凤山气田致密凝析气藏CO_(2)吞吐效果评价
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作者 高云丛 王建波 周杨 《大庆石油地质与开发》 CAS 北大核心 2024年第2期160-167,共8页
长岭断陷龙凤山气田致密凝析气藏产量递减快,采出程度低,为了减弱近井地带反凝析污染现象和凝析油采出困难的开发难题,通过数值模拟方法和注CO_(2)吞吐实验,分析评价CO_(2)吞吐效果,探讨提高气井产量和气藏采收率的方法。结果表明:与注... 长岭断陷龙凤山气田致密凝析气藏产量递减快,采出程度低,为了减弱近井地带反凝析污染现象和凝析油采出困难的开发难题,通过数值模拟方法和注CO_(2)吞吐实验,分析评价CO_(2)吞吐效果,探讨提高气井产量和气藏采收率的方法。结果表明:与注干气吞吐相比,致密凝析气藏注CO_(2)吞吐更能较为有效地解除反凝析污染;气井反凝析分为反凝析初期(对生产基本无影响)、反凝析加重(对油生产有影响)、反凝析严重(对油气生产影响大)、极端反凝析(几乎不出油)共4个阶段;不同反凝析特征阶段的气井CO_(2)吞吐机理和目的不同,CO_(2)吞吐参数应当相应优化。现场实施表明,注CO_(2)吞吐的5口井在吞吐前处于不同的反凝析阶段,吞吐后取得了快速增加地层能量、解堵近井地带反凝析污染、提高注入能力、增加凝析油和天然气产量等效果。研究成果可为CO_(2)吞吐技术在致密凝析气藏的规模应用提供了经验。 展开更多
关键词 致密凝析气藏 CO_(2)吞吐 参数优化设计 现场试验 效果评价 龙凤山气田 长岭断陷
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Inelastic displacement ratio of low-to mid-rise BRBFs designed under variable levels of seismicity 被引量:1
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作者 Hamdy Abou-Elfath Mostafa Ramadan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期763-775,共13页
Buckling-restrained braces(BRBs)have shown their capability to provide building structures with stiffness,strength,and ductility.Estimating the seismic drifts of buckling-restrained braced frames(BRBFs)is an important... Buckling-restrained braces(BRBs)have shown their capability to provide building structures with stiffness,strength,and ductility.Estimating the seismic drifts of buckling-restrained braced frames(BRBFs)is an important design step to control structural and non-structural damage.In current practice of seismic design,the estimation of seismic drifts of BRBFs is performed by using empirical calculations that are independent upon either the type of the structural system or the design level of seismicity.In these empirical calculations,the seismic drifts are estimated by amplifying the reduced elastic drifts obtained under design lateral loading with a displacement amplification factor(DAF).The value of DAF is considered equal to the product of the response modification factor R and the inelastic displacement ratioρ.The goal of the current research is to assess the value ofρfor low-to mid-rise BRBFs designed under low and high levels of seismicity.This goal has been achieved by conducting a series of elastic and inelastic time-history analyses pertaining to an ensemble of earthquake records on 3-,6-and 9-story BRBFs.The results indicate that theρ-ratio increases with an increase in design seismic intensity and an increase in experienced inelasticity.The range ofρfor low seismicity designs ranges from 0.63 to 0.9,while for high seismicity designs this range stretches from 0.83 to 1.29.It has been found that the consideration of a generalρ-ratio of 1.0 is a reasonable estimation for the design of the BRBFs considered in this study. 展开更多
关键词 displacement amplification factor inelastic displacement ratio SEISMICITY buckling-restrained brace seismic drift seismic design
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职业教育“2+2+2”贯通培养模式的生成逻辑、内涵特征与实施路径 被引量:1
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作者 马良军 孙光明 +1 位作者 谢琴 刘淑静 《工业技术与职业教育》 2024年第1期71-77,共7页
职业教育“2+2+2”贯通培养模式是河北省推动职业教育人才培养改革的实践创新,是凸显职业教育类型特征、拓宽学生成长成才通道、提升人才培养质量的重要途径。在梳理“2+2+2”贯通培养模式的生成逻辑、分析其内涵特征的基础上,以河北交... 职业教育“2+2+2”贯通培养模式是河北省推动职业教育人才培养改革的实践创新,是凸显职业教育类型特征、拓宽学生成长成才通道、提升人才培养质量的重要途径。在梳理“2+2+2”贯通培养模式的生成逻辑、分析其内涵特征的基础上,以河北交通职业技术学院电气自动化技术专业“2+2+2”贯通培养项目为例,提出其实施路径,包括:建立多主体贯通培养架构,一体化设计衔接育人标准体系,校企共同打造高水平双导师团队,校企共同开发优质教学资源,创新工学交替教学模式和构建教学运行质量保证体系。 展开更多
关键词 2+2+2”贯通培养 类型特征 一体化设计
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Computational design of promising 2D electrode materials for Li-ion and Li–S battery applications 被引量:1
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作者 Ke Fan Yuen Hong Tsang Haitao Huang 《Materials Reports(Energy)》 2023年第3期1-23,共23页
Lithium-ion batteries(LIBs)and lithium-sulfur(Li–S)batteries are two types of energy storage systems with significance in both scientific research and commercialization.Nevertheless,the rational design of electrode m... Lithium-ion batteries(LIBs)and lithium-sulfur(Li–S)batteries are two types of energy storage systems with significance in both scientific research and commercialization.Nevertheless,the rational design of electrode materials for overcoming the bottlenecks of LIBs and Li–S batteries(such as low diffusion rates in LIBs and low sulfur utilization in Li–S batteries)remain the greatest challenge,while two-dimensional(2D)electrodes materials provide a solution because of their unique structural and electrochemical properties.In this article,from the perspective of ab-initio simulations,we review the design of 2D electrode materials for LIBs and Li–S batteries.We first propose the theoretical design principles for 2D electrodes,including stability,electronic properties,capacity,and ion diffusion descriptors.Next,classified examples of promising 2D electrodes designed by theoretical simulations are given,covering graphene,phosphorene,MXene,transition metal sulfides,and so on.Finally,common challenges and a future perspective are provided.This review paves the way for rational design of 2D electrode materials for LIBs and Li–S battery applications and may provide a guide for future experiments. 展开更多
关键词 Lithium-ion batteries Lithium-sulfur batteries 2D electrode materials Computational design
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低渗透油藏注CO_(2)混相驱及CO_(2)埋存评价 被引量:1
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作者 侯大力 龚凤鸣 +3 位作者 陈涛 孙雷 赵锐 苏杰 《大庆石油地质与开发》 CAS 北大核心 2024年第1期59-67,共9页
注CO_(2)开发低渗透油藏不仅能增加原油采收率,还能将CO_(2)埋存在地下,实现双赢。为了明确X低渗透油藏注CO_(2)混相驱油机理、CO_(2)在地层中的运移规律以及埋存机理,利用实验和数值模拟相结合的方法,从注CO_(2)混相特征、注CO_(2)参... 注CO_(2)开发低渗透油藏不仅能增加原油采收率,还能将CO_(2)埋存在地下,实现双赢。为了明确X低渗透油藏注CO_(2)混相驱油机理、CO_(2)在地层中的运移规律以及埋存机理,利用实验和数值模拟相结合的方法,从注CO_(2)混相特征、注CO_(2)参数优化和CO_(2)埋存评价3方面对X低渗透油藏进行研究。结果表明:地层原油注CO_(2)最小混相压力为26.03 MPa,CO_(2)有降低原油黏度和密度的作用;通过参数优化确定的推荐注采方案与衰竭开采相比,累计增油量为96.21×10^(4)t,主力开发层系X4⁃2、X4⁃3提高采收率分别为9.37百分点、6.02百分点;CO_(2)注入地层后,随着时间的推移,在平面上不断向四周扩散,在纵向上受重力分异的作用向上运移;评价区块注CO_(2)驱推荐方案预计CO_(2)埋存量为68.08×10^(4)t,其中构造埋存量、束缚埋存量、溶解埋存量和矿化埋存量分别为42.20×10^(4)、17.79×10^(4)、6.24×10^(4)和1.85×10^(4)t。研究成果为低渗透油藏注CO_(2)驱及CO_(2)埋存提供了实验和理论的借鉴意义。 展开更多
关键词 低渗透油藏 CO_(2)驱油与埋存 方案设计 参数优化 埋存评价
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细粒砂矿物成分及粒径配比对CO_(2)水合物合成特性影响的实验研究
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作者 马越 赵建忠 +1 位作者 高强 张驰 《低碳化学与化工》 CAS 北大核心 2024年第4期124-130,共7页
在冻土层中用水合物法封存CO_(2)是一种具有潜力和前景的CO_(2)封存技术。为探究地层性质对CO_(2)封存的影响,在初始压力5.5 MPa、温度1.27℃的条件下,在不同细粒砂矿物成分及粒径配比的影响下进行了CO_(2)水合物合成实验,对实验过程中C... 在冻土层中用水合物法封存CO_(2)是一种具有潜力和前景的CO_(2)封存技术。为探究地层性质对CO_(2)封存的影响,在初始压力5.5 MPa、温度1.27℃的条件下,在不同细粒砂矿物成分及粒径配比的影响下进行了CO_(2)水合物合成实验,对实验过程中CO_(2)水合物生成过程的压力-温度变化、CO_(2)水合物平均生成速率、CO_(2)耗气量和相饱和度等进行了分析。结果表明,细粒砂与粗粒砂粒径配比(各组分质量比,下同)为1.0:2.0时的CO_(2)水合物平均生成速率最小(12.60 mmol/min),随着粗粒砂比例的增大,比表面积减少,CO_(2)水合物平均生成速率变慢。蒙脱石黏土不利于CO_(2)水合物生成,粉砂组(含细粒砂与粗粒砂)CO_(2)水合物平均生成速率高于粉砂质黏土组(含细粒砂和蒙脱石黏土),且粉砂组实验更容易实现高的水合物饱和度和CO_(2)耗气量,因此在矿物成分含细粒砂与粗粒砂的区域更适合进行CO_(2)封存。细粒砂与粗粒砂或黏土矿物粒径配比为1.0:0.5时的CO_(2)耗气量分别为0.86 mol、0.77 mol,随着粗粒砂和黏土矿物比例的增大,水合物相饱和度和CO_(2)耗气量均逐渐减小,细粒砂与粗粒砂或黏土矿物粒径配比为1.0:0.5时是适合水合物法封存CO_(2)的比例。 展开更多
关键词 CO_(2) 水合物 碳封存 黏土 粒径配比
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High-Con cent rat ion Electrosynthesis of Formic Acid/Formate from CO_(2):Reactor and Electrode Design Strategies
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作者 Yizhu Kuang Hesamoddin Rabiee +4 位作者 Lei Ge Thomas E.Rufford Zhiguo Yuan John Bell Hao Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期141-157,共17页
The electrochemical CO_(2)reduction reaction(CO_(2)RR),driven by renewable energy,provides a potential carbon-neutral avenue to convert CO_(2)into valuable fuels and feedstocks.Conversion of CO_(2)into formic acid/for... The electrochemical CO_(2)reduction reaction(CO_(2)RR),driven by renewable energy,provides a potential carbon-neutral avenue to convert CO_(2)into valuable fuels and feedstocks.Conversion of CO_(2)into formic acid/formate is considered one of the economical and feasible methods,owing to their high energy densities,and ease of distribution and storage.The separation of formic acid/formate from the reaction mixtures accounts for the majority of the overall CO_(2)RR process cost,while the increment of product concentration can lead to the reduction of separation cost,remarkably.In this paper,we give an overview of recent strategies for highly concentrated formic acid/formate products in CO_(2)RR.CO_(2)RR is a complex process with several different products,as it has different intermediates and reaction pathways.Therefore,this review focuses on recent study strategies that can enhance targeted formic acid/formate yield,such as the all-solid-state reactor design to deliver a high concentration of products during the reduction of CO_(2)in the electrolyzer.Firstly,some novel electrolyzers are introduced as an engineering strategy to improve the concentration of the formic acid/formate and reduce the cost of downstream separations.Also,the design of planar and gas diffusion electrodes(GDEs)with the potential to deliver high-concentration formic acid/formate in CO_(2)RR is summarized.Finally,the existing technological challenges are highlighted,and further research recommendations to achieve high-concentration products in CO_(2)RR.This review can provide some inspiration for future research to further improve the product concentration and economic benefits of CO_(2)RR. 展开更多
关键词 electrochemical CO_(2)reduction reaction electrode design formic acid/formate high-concentration reactor design
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Comparative efficacy of sodium glucose cotransporter-2 inhibitors in the management of type 2 diabetes mellitus:A real-world experience 被引量:1
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作者 Lubna Islam Dhanya Jose +3 位作者 Mohammed Alkhalifah Dania Blaibel Vishnu Chandrabalan Joseph M Pappachan 《World Journal of Diabetes》 SCIE 2024年第3期463-474,共12页
BACKGROUND Sodium glucose cotransporter-2 inhibitors(SGLT-2i)are a class of drugs with modest antidiabetic efficacy,weight loss effect,and cardiovascular benefits as proven by multiple randomised controlled trials(RCT... BACKGROUND Sodium glucose cotransporter-2 inhibitors(SGLT-2i)are a class of drugs with modest antidiabetic efficacy,weight loss effect,and cardiovascular benefits as proven by multiple randomised controlled trials(RCTs).However,real-world data on the comparative efficacy and safety of individual SGLT-2i medications is sparse.AIM To study the comparative efficacy and safety of SGLT-2i using real-world clinical data.METHODS We evaluated the comparative efficacy data of 3 SGLT-2i drugs(dapagliflozin,canagliflozin,and empagliflozin)used for treating patients with type 2 diabetes mellitus.Data on the reduction of glycated hemoglobin(HbA1c),body weight,blood pressure(BP),urine albumin creatinine ratio(ACR),and adverse effects were recorded retrospectively.RESULTS Data from 467 patients with a median age of 64(14.8)years,294(62.96%)males and 375(80.5%)Caucasians were analysed.Median diabetes duration was 16.0(9.0)years,and the duration of SGLT-2i use was 3.6(2.1)years.SGLT-2i molecules used were dapagliflozin 10 mg(n=227;48.6%),canagliflozin 300 mg(n=160;34.3%),and empagliflozin 25 mg(n=80;17.1).Baseline median(interquartile range)HbA1c in mmol/mol were:dapagliflozin-78.0(25.3),canagliflozin-80.0(25.5),and empagliflozin-75.0(23.5)respectively.The respective median HbA1c reduction at 12 months and the latest review(just prior to the study)were:66.5(22.8)&69.0(24.0),67.0(16.3)&66.0(28.0),and 67.0(22.5)&66.5(25.8)respectively(P<0.001 for all comparisons from baseline).Significant improvements in body weight(in kilograms)from baseline to study end were noticed with dapagliflozin-101(29.5)to 92.2(25.6),and canagliflozin 100(28.3)to 95.3(27.5)only.Significant reductions in median systolic and diastolic BP,from 144(21)mmHg to 139(23)mmHg;(P=0.015),and from 82(16)mmHg to 78(19)mmHg;(P<0.001)respectively were also observed.A significant reduction of microalbuminuria was observed with canagliflozin only[ACR 14.6(42.6)at baseline to 8.9(23.7)at the study end;P=0.043].Adverse effects of SGLT-2i were as follows:genital thrush and urinary infection-20(8.8%)&17(7.5%)with dapagliflozin;9(5.6%)&5(3.13%)with canagliflozin;and 4(5%)&4(5%)with empagliflozin.Diabetic ketoacidosis was observed in 4(1.8%)with dapagliflozin and 1(0.63%)with canagliflozin.CONCLUSION Treatment of patients with SGLT-2i is associated with statistically significant reductions in HbA1c,body weight,and better than those reported in RCTs,with low side effect profiles.A review of large-scale real-world data is needed to inform better clinical practice decision making. 展开更多
关键词 Sodium glucose cotransporter-2 inhibitors Empagliflozin Canagliflozin DAPAGLIFLOZIN Type 2 diabetes mellitus Cardiovascular disease Albumin creatinine ratio DIABESITY
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Optical design of vertical edge Thomson scattering on HL-2M tokamak
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作者 龚少博 石中兵 +9 位作者 周艺轩 张通川 高金明 郑典麟 孙平 于利明 陈伟 钟武律 许敏 段旭如 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第7期97-103,共7页
A vertical edge Thomson scattering(ETS) diagnostic system on HL-2M tokamak has been designed.The ETS system collects the scattered light from Nd:YAG laser(1064 nm,2 J,30 Hz,15 ns).The laser beam propagates vertically ... A vertical edge Thomson scattering(ETS) diagnostic system on HL-2M tokamak has been designed.The ETS system collects the scattered light from Nd:YAG laser(1064 nm,2 J,30 Hz,15 ns).The laser beam propagates vertically through the plasma region and the polarization is parallel to the toroidal magnetic field.A special designed Galileo-type telescope with long Rayleigh length is applied to focus the laser size and ensure collimation.A group of doubleGaussian collection lenses image the 600 mm vertical scattered region onto rectangular fiber arrays with a spatial resolution of 10 mm.The 2.20 mm × 2.86 mm fiber optic bundle consists of 130 low hydroxyl(OH) 200/220 μm(core/cladding) diameter fibers with numerical aperture NA=0.22,carrying the light to remotely located multi-channel polychromators.Effect of oblique incidence on narrow band filter has been analyzed.The designed electron temperatures range from 5 to 1000 eV and electron densities from 5 × 10^(18) to 1×10^(20) m^(-3). 展开更多
关键词 edge Thomson scattering optical design HL-2M
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45钢表面激光熔覆Mo_(2)FeB_(2)涂层的工艺参数优化研究
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作者 崔梓涵 潘应君 +1 位作者 张浩 柯德庆 《武汉科技大学学报》 CAS 北大核心 2024年第5期347-354,共8页
本文探究了利用激光熔覆技术在45钢表面制备Mo_(2)FeB_(2)涂层的工艺参数优化问题。采用田口法设计正交实验,选取激光功率、扫描速度、送粉速率作为工艺参数,以稀释率和显微硬度作为评估成型质量的响应目标,通过信噪比和方差分析研究了... 本文探究了利用激光熔覆技术在45钢表面制备Mo_(2)FeB_(2)涂层的工艺参数优化问题。采用田口法设计正交实验,选取激光功率、扫描速度、送粉速率作为工艺参数,以稀释率和显微硬度作为评估成型质量的响应目标,通过信噪比和方差分析研究了工艺参数和响应目标的关系,并结合灰色关联分析进行工艺参数优化,得到最佳工艺参数组合为:激光功率5000 W、扫描速度13.6 mm/s、送粉速率15 g/s。使用这一参数组合进行激光熔覆实验,结果显示,相比于正交实验得到的结果,两个响应目标均有所改善,涂层质量显著提升,验证了田口-灰色关联方法的可靠性。 展开更多
关键词 激光熔覆 参数优化 Mo_(2)FeB_(2) 田口设计 灰色关联
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