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Decentralized Semi-Supervised Learning for Stochastic Configuration Networks Based on the Mean Teacher Method
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作者 Kaijing Li Wu Ai 《Journal of Computer and Communications》 2024年第4期247-261,共15页
The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy ... The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy of decentralized SCN algorithms while effectively protecting user privacy. To this end, we propose a decentralized semi-supervised learning algorithm for SCN, called DMT-SCN, which introduces teacher and student models by combining the idea of consistency regularization to improve the response speed of model iterations. In order to reduce the possible negative impact of unsupervised data on the model, we purposely change the way of adding noise to the unlabeled data. Simulation results show that the algorithm can effectively utilize unlabeled data to improve the classification accuracy of SCN training and is robust under different ground simulation environments. 展开更多
关键词 Stochastic Neural Network Consistency Regularization semi-Supervised Learning Decentralized Learning
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Investigation on activated semi-coke desulfurization 被引量:7
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作者 SHANGGUANJu LIZhuan-li LIChun-hu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第1期91-94,共4页
An activated semi coke with industrial scale size was prepared by high pressure hydrothermal chemistry activation, HNO 3 oxidation and calcination activation in proper order from Inner Mongolia Zhalainuoer semi coke, ... An activated semi coke with industrial scale size was prepared by high pressure hydrothermal chemistry activation, HNO 3 oxidation and calcination activation in proper order from Inner Mongolia Zhalainuoer semi coke, which is rich in resource and cheap in sale. SO 2 adsorption capacity on this activated semi coke was assessed in the fixed bed in the temperature range of 60—170℃, space velocity range of 500—1300 h -1 , SO 2 concentration of 1000—3000 ppmv, and N 2 as balance. The surface area, elemental and proximate analysis for both raw semi coke and activated semi cokes were measured. The experimental results showed that the activated semi coke has a high adsorption capacity for sulfur dioxide than the untreated semi coke. This may be the result of increase of surface area on activated semi coke and surface oxygen functional groups with basicity characteristics. Comparison to result of FTIR, it is known that group of —C—O—C? ?may be active center of SO 2 catalytic adsorption on activated semi coke. 展开更多
关键词 activated semi-coke high pressure hydrothermal chemistry ACTIVATION DESULFURIZATION
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Impact of impregnation pressure on desulfurization performance of Zn-based sorbents supported on semi-coke 被引量:10
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作者 Xianrong Zheng Weiren Bao +3 位作者 Qingmai Jin Ruiyuan He Liping Chang Kechang Xie 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第1期56-60,共5页
High-pressure impregnation, a new preparation method for sorbents to remove H2S from hot coal gas, is introduced in this paper. Semi-coke (SC) and ZnO is selected as the support and active component of sorbent, resp... High-pressure impregnation, a new preparation method for sorbents to remove H2S from hot coal gas, is introduced in this paper. Semi-coke (SC) and ZnO is selected as the support and active component of sorbent, respectively. The sorbent preparation process includes high-pressure impregnation, filtration, ovendry and calcination. The aim of this research is to primarily study the effects of the impregnation pressure on physical properties and desulfurization ability of the sorbent. The desulfurization experiment was carried out in a fixed-bed reactor at 500 ~C and a simulated coal gas used in this work was composed of CO (33 vol%), H2 (39 vol%), H2S (300 ppm in volume), and N2 (balance). Experimental results show that the pore structure of the SC support can be improved effectively and ZnO active component can be uniformly dispersed on the support, with the small particle size of 10-500 nm. Sorbents prepared using high-pressure impregnation have better desulfurization capacity and their active components have higher utilization rate. P20-ZnSC sorbent, obtained by high-pressure impregnation at 20 atm, has the best desulfurization ability with a sulfur capacity of 7.54 g S/100g sorbent and a breakthrough time of 44 h. Its desulfurization precision and efficiency of removing H2S from the middle temperature gases can reach 〈 1 ppm and 〉99.7%, respectively, before sorbent breakthrough. 展开更多
关键词 DESULFURIZATION high-pressure impregnation method semi-coke support ZnO sorbent
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Combustion characteristics of Daqing oil shale and oil shale semi-cokes 被引量:8
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作者 MIAO Zhen-yong WU Ouo-guang LI Ping ZHAO Na WANG Pan-cheng MENG Xian-liang 《Mining Science and Technology》 EI CAS 2009年第3期380-384,共5页
Thermo-gravimetric-analysis(TGA) was used to analyze the combustion characteristics of an oil shale and semi-cokes prepared from it.The effect of prior pyrolysis and TGA heating rate on the combustion process was stud... Thermo-gravimetric-analysis(TGA) was used to analyze the combustion characteristics of an oil shale and semi-cokes prepared from it.The effect of prior pyrolysis and TGA heating rate on the combustion process was studied.Prior pyrolysis affects the initial temperature of mass loss and the ignition temperature.The ignition temperature increases as the volatile content of the sample decreases.TG/DTG curves obtained at different heating rates show that heating rate has little effect on ignition temperature.But the peak of combustion shifts to higher temperatures as the heating rate is increased.The Coats-Redfern integration method was employed to find the combustion-reaction kinetic parameters for the burning of oil shale and oil shale semi-coke. 展开更多
关键词 燃烧特性 油页岩 半焦 反应动力学参数 升温速率 大庆 点火温度 质量损失
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Effects of ultrasound on the desulfurization performance of hot coal gas over Zn-Mn-Cu supported on semi-coke sorbent prepared by high-pressure impregnation method 被引量:4
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作者 Xiaoyang Zhang Xianrong Zheng +2 位作者 Peng Han Ze Liu Liping Chang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第3期291-298,共8页
Zn-Mn-Cu/SC(U) sorbent was hydrothermally synthesized by ultrasound-assisted high-pressure impregnation method with semi-coke(SC)as support and the mixed solution of zinc nitrate,manganese nitrate and copper nitra... Zn-Mn-Cu/SC(U) sorbent was hydrothermally synthesized by ultrasound-assisted high-pressure impregnation method with semi-coke(SC)as support and the mixed solution of zinc nitrate,manganese nitrate and copper nitrate as active component precursors.The desulfurization performances of hot coal gas on the prepared sorbent at a mid-temperature of 500°C were tested in fixed-bed reactor.Morphology and pore structure of the prepared sorbent were also characterized by TEM,N2adsorption/desorption isotherms and XRD.For comparison,the sorbent of Zn-Mn-Cu/SC prepared by conventional high-pressure impregnation was also evaluated and characterized in order to study the effects of ultrasound treatment.Zn-Mn-Cu/SC(U) sorbent prepared by high-pressure impregnation under ultrasound-assisted condition showed a better desulfurization performance than Zn-Mn-Cu/SC.It could remove H2 S from 1000×10-6m3/m3 to 0.1×10-6m3/m3 at 500°C and maintained for 12.5 h with the sulfur capacity of 7.74%,in which both the breakthrough time and sulfur capacity were about 32% and 51% higher than those of Zn-Mn-Cu/SC sorbent.The introduction of ultrasound during high-pressure impregnation process greatly improved the morphology and pore structure of the sorbent.The ultrasonic treatment made particle size of active components smaller and made them more evenly disperse on semi-coke support,which provided more opportunities to contact with H2S in coal-based gases.However,there were no any difference in compositions and existing forms of active components on the Zn-Mn-Cu/SC and Zn-Mn-Cu/SC(U) sorbents. 展开更多
关键词 ultrasound-assistance high-pressure impregnation mid-temperature desulfurization Zn-Mn-Cu sorbent semi-coke support
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Effects of process parameters on pore structure of semi-coke prepared by solid heat carrier with dry distillation 被引量:20
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作者 Zhou, Guoli Wu, Jianjun +5 位作者 Miao, Zhenyong Hu, Xuelian Li, Xia Shi, Xin Cai, Zhidan Shang, Yukun 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期423-427,共5页
The semi-coke was prepared by solid heat carrier with dry distillation in single factor method. The pore structures of raw coal and semi-coke were characterized by Brunauer-Emmett-Teller (BET) and scanning electron mi... The semi-coke was prepared by solid heat carrier with dry distillation in single factor method. The pore structures of raw coal and semi-coke were characterized by Brunauer-Emmett-Teller (BET) and scanning electron microscope (SEM). The results show that the adsorption and desorption isotherm of semi-coke are not coincident. There was a wide pore distribution on the semi-coke, in which mesopores and micropores account for a considerable proportion. Also there are many more secondary pores. With the increase of the final temperature of heat carrier and constant temperature, as well as the decrease of volume ratio of coal and hot carrier reactor, specific surface area and pore volume of semi-coke increased rapidly first and then decreased and finally increased, along with the rapidly reduction of average pore size. SEM photos show that the surface of semi-coke becomes increasingly rough and glossy. 展开更多
关键词 semi-coke Pore structure Heat carrier dry distillation BET SEM
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Process optimization for treatment of methyltin mercaptide effluents using modified semi-coke 被引量:1
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作者 王欣 C.Srinivasakannan +4 位作者 曲雯雯 彭金辉 张利波 段昕辉 卢帅丹 《Journal of Central South University》 SCIE EI CAS 2013年第12期3633-3640,共8页
The central composite process optimization was performed by response surface methodology technique using a design for the treatment of methyltin mercaptide with modified semi-coke. The semi-coke from the coal industry... The central composite process optimization was performed by response surface methodology technique using a design for the treatment of methyltin mercaptide with modified semi-coke. The semi-coke from the coal industry was suitably modified by treating it with phosphoric acid, with a thermal activation process. The objective of the process optimization is to reduce the chemical oxygen demand(COD) and 4NH—N in the methyltin mercaptide industrial effluent. The process variables considered for process optimization are the semi-coke dosage, adsorption time and effluent pH. The optimized process conditions are identified to be a semi-coke dosage of 80 g/L, adsorption time of 90 min and a pH value of 8.34. The ANOVA results indicate that the adsorbent dosage and pH are the significant parameters, while the adsorption time is insignificant, possibly owing to the large range of adsorption time chosen. The textural characteristics of modified semi-coke were analyzed using scanning electron microscopy and nitrogen adsorption isotherm. The average BET surface area of modified semi-coke is estimated to be 915 m2/g, with the average pore volume of 0.71 cm3/g and a average pore diameter of 3.09 nm, with micropore volume contributing to 52.36%. 展开更多
关键词 流程优化 工业废水 甲基锡 改性 硫醇 半焦 吸附时间 平均孔径
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SEMI标准在半导体制造设备中的应用 被引量:2
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作者 韦薇 林煦呐 +2 位作者 张帅 谢琼 杨师 《电子工业专用设备》 2023年第2期58-63,共6页
SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料... SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料的使用效率标准、SECS/GEM通讯标准及其研究应用现状;提出了我国半导体产业的快速发展需要加大SEMI标准的普及应用。 展开更多
关键词 半导体制造设备 semi S2标准 semi F47标准
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Characterization of semi-coke generated by coal-based direct reduction process of siderite
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作者 朱德庆 罗艳红 +1 位作者 潘建 周仙霖 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2914-2921,共8页
Solid wastes derived from metallurgical industries pose a significant threat to environment. The utilization and disposal of these solid wastes are the major concern in the world. Semi-coke generated in coal-based dir... Solid wastes derived from metallurgical industries pose a significant threat to environment. The utilization and disposal of these solid wastes are the major concern in the world. Semi-coke generated in coal-based direct reduction process of iron ore is a by-product and its suitable utilization is not available so far. In order to handle it properly, the characteristics of this by-product were comprehensively investigated. A series of analysis methods were used to demonstrate its mineral compositions, petrography and physico-chemical properties. The results reveal that the semi-coke has poor washability. The fixed carbon content of semi-coke reaches 76.11% and the gross calorific value is 28.10 MJ/kg, both of which are similar to those of traditional sinter coke breeze. Also, semi-coke ash possesses lower content of SiO2, Al2O3, S and higher content of CaO and MgO, which could improve the strength of sinter ore when partially substituting for coke breeze in sintering. Semi-coke features well-development porous structure and higher reaction activity, which predicts that the sintering speed could be elevated to some extent when employing it as a partial replacement of coke breeze, so the studies further suggest that the potential adverse effect of the high reactivity on sintering process could be weakened by adequately coarsening the semi-coke's particle size. 展开更多
关键词 还原过程 半焦 煤基 表征 矿产 物理化学性质 固体废物 烧结过程
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The Delivery of Grand Multiparas in a Semi-Rural Setting: A Cross-Sectional Descriptive Study at the Ayos Locality of Cameroon
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作者 Serge Robert Nyada Cliford E. Ebong +6 位作者 Véronique Mboua Christiane Nsahlai Pascale Mpono Emenguele Michelle Mendoua Junie Metogo Isidore Tompeen Cyrile Claude Noa Ndoua 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第1期74-81,共8页
Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the materni... Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the maternity of the regional hospital annex of Ayos, a semi-rural locality in the Center region of Cameroon. The study covered the period from January 2012 through December 2020, and the objective was to assess the frequency, the determinants and the outcome of delivery in grand multiparas. Results: We recorded 1384 deliveries and enrolled 137 cases of delivery of grand multiparas. This gives a frequency of grand multipara delivery of 9.89%. The mean age of the women was 34.96 ± 4.45 years. Married parturients accounted for 65% of the cases and 16.8% were HIV positive. Delivery occurred at term in 89.9%. In 35.8%, no antenatal consultation was done. The use of the partograph during labor was reported in 11.7%. Per vaginal delivery was noted in 88.3%, emergency cesarean in 10.2% and elective cesarean in 1.5%. The most frequent maternal complications included post-partum hemorrhage (19.9%), genital tract tears (12.4%), endometritis (9.5%) and surgical wound infection (8.7%). No maternal death was recorded. The mean birth weight of the newborns was 3336.8 ± 550 g. Fetal complications were mostly represented by neonatal infection (20.1%), perinatal death (7.9%) and neonatal asphyxia (9.5%). Conclusion: The frequency of grand multiparous delivery in the semi-rural locality of Ayos, Cameroon, was 9.89%. The mean age of parturients was 38.96 years and the proportion of vaginal delivery was 88.3%. 展开更多
关键词 Grand Multipara Delivery semi Rural Cameroon
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基于多核CPU的无锁并行Semi-naive算法
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作者 喻婷 王立松 秦小麟 《计算机科学》 CSCD 北大核心 2023年第6期29-35,共7页
Datalog系统被广泛应用于很多领域,如图数据库、网络和静态程序分析等。在处理海量数据时,基于串行的Datalog求解策略无法充分发挥现有多核处理器的计算性能。针对上述问题,提出一种基于多核CPU的无锁并行Semi-naive算法(Parallel Semi-... Datalog系统被广泛应用于很多领域,如图数据库、网络和静态程序分析等。在处理海量数据时,基于串行的Datalog求解策略无法充分发挥现有多核处理器的计算性能。针对上述问题,提出一种基于多核CPU的无锁并行Semi-naive算法(Parallel Semi-naive, PSN)用于支持Datalog的高效求解。PSN使用B+树索引进行数据划分,将数据分配给不同的线程执行计算,每个分区产生的中间结果元组互不相同,有利于实现计算时无锁的并行。同时提出一种双层哈希表结构来索引中间结果以提高查重的效率,每个线程只在特定的区域执行相关的计算,无需使用锁来防止写冲突。PSN使用任务队列-线程池为空闲线程分配任务,来实现多线程的负载均衡。在KONECT(Koblenz Network Collection)及斯坦福SNAP(Stanford Network Analysis Platform)的公开数据集上的实验结果表明,PSN算法可以优化Datalog规则的查询性能。 展开更多
关键词 DATALOG semi-naive算法 并行 递归规则 负载均衡
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不同有机肥对土壤及核桃果实品质的影响
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作者 李艳 王芳 +4 位作者 陈燕燕 张文龙 张锐 王红霞 安秀红 《中国南方果树》 北大核心 2024年第2期178-185,共8页
为探究“辽宁1号”核桃较适宜的有机肥,在河北省隆尧县红沙峪生态农业科技有限公司核桃园以10年生“辽宁1号”核桃树为试验材料,利用半焦肥、鸡粪及生物菌肥3种有机肥进行施肥处理,检测不同有机肥对土壤性状、核桃产量和品质的影响。结... 为探究“辽宁1号”核桃较适宜的有机肥,在河北省隆尧县红沙峪生态农业科技有限公司核桃园以10年生“辽宁1号”核桃树为试验材料,利用半焦肥、鸡粪及生物菌肥3种有机肥进行施肥处理,检测不同有机肥对土壤性状、核桃产量和品质的影响。结果表明,生物菌肥(2.5 kg/株)能显著提高种仁黄酮含量;鸡粪(40 kg/株)能显著提高种仁Fe、Zn含量以及土壤速效磷、速效钾含量;5.0 kg/株半焦肥能显著提高种仁多酚、土壤有机质含量;10.0 kg/株半焦肥施肥能显著提高青果的横径,坚果的单果质量、纵径、横径、侧径,种仁的脂肪、K、Ca、Mn、Cu含量以及土壤全磷含量。10.0 kg/株半焦肥在相关果实品质方面的综合效果最好,而5.0 kg/株半焦肥的经济效益最高。 展开更多
关键词 核桃 半焦肥 鸡粪 生物菌肥 土壤 果实品质
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Radar emitter signal recognition method based on improved collaborative semi-supervised learning
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作者 JIN Tao ZHANG Xindong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1182-1190,共9页
Rare labeled data are difficult to recognize by using conventional methods in the process of radar emitter recogni-tion.To solve this problem,an optimized cooperative semi-supervised learning radar emitter recognition... Rare labeled data are difficult to recognize by using conventional methods in the process of radar emitter recogni-tion.To solve this problem,an optimized cooperative semi-supervised learning radar emitter recognition method based on a small amount of labeled data is developed.First,a small amount of labeled data are randomly sampled by using the bootstrap method,loss functions for three common deep learning net-works are improved,the uniform distribution and cross-entropy function are combined to reduce the overconfidence of softmax classification.Subsequently,the dataset obtained after sam-pling is adopted to train three improved networks so as to build the initial model.In addition,the unlabeled data are preliminarily screened through dynamic time warping(DTW)and then input into the initial model trained previously for judgment.If the judg-ment results of two or more networks are consistent,the unla-beled data are labeled and put into the labeled data set.Lastly,the three network models are input into the labeled dataset for training,and the final model is built.As revealed by the simula-tion results,the semi-supervised learning method adopted in this paper is capable of exploiting a small amount of labeled data and basically achieving the accuracy of labeled data recognition. 展开更多
关键词 emitter signal identification time series BOOTSTRAP semi supervised learning cross entropy function homogeniza-tion dynamic time warping(DTW)
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硅铁冶炼用兰炭的调控制备与工业应用试验
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作者 王毅 邹冲 +4 位作者 马成 李彦雄 李彬 李信 李磊 《铁合金》 CAS 2024年第1期19-26,共8页
介绍了硅铁冶炼用兰炭的调控制备方法,考察了依据调控制备方法生产的兰炭在硅铁冶炼中的应用,通过对调控制备兰炭的质量检测和其入硅铁炉后的冶炼指标进行追踪分析,证实了调控制备方法的可行性。试验结果表明:以优选原煤、调整干馏工艺... 介绍了硅铁冶炼用兰炭的调控制备方法,考察了依据调控制备方法生产的兰炭在硅铁冶炼中的应用,通过对调控制备兰炭的质量检测和其入硅铁炉后的冶炼指标进行追踪分析,证实了调控制备方法的可行性。试验结果表明:以优选原煤、调整干馏工艺参数和入炉还原剂再优化为手段的调控制备方法可以稳定兰炭的质量,并有效降低硅铁冶炼电耗;通过对原煤热解兰炭的性能评估可预测其工业兰炭的性能,从而优选出可生产适宜硅铁冶炼用兰炭的原煤;通过优选原煤和调控干馏炉参数可生产出成分和性质稳定的高性能硅铁冶炼用兰炭。 展开更多
关键词 兰炭 硅铁 工业应用
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煤制兰炭过程中挥发性有机污染物和臭氧协同处理机理
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作者 张蕾 陈雅 +1 位作者 贾阳 黄鹏程 《西安科技大学学报》 CAS 北大核心 2024年第1期135-143,共9页
为探究低温等离子体联合催化剂载体协同处理煤制兰炭过程中产生的挥发性有机污染物及臭氧,以二甲苯作为目标污染物,选取γ-氧化铝小球为催化剂载体,考察功率、氧通量、二甲苯初始浓度、催化剂载体用量等因素对挥发性有机污染物和臭氧协... 为探究低温等离子体联合催化剂载体协同处理煤制兰炭过程中产生的挥发性有机污染物及臭氧,以二甲苯作为目标污染物,选取γ-氧化铝小球为催化剂载体,考察功率、氧通量、二甲苯初始浓度、催化剂载体用量等因素对挥发性有机污染物和臭氧协同处理效果的影响。结果表明:低温等离子体放电功率越大,二甲苯的脱除效果越好;在放电功率为70 W、氧通量为15%、初始浓度为600×10^(-6)时,二甲苯的去除率为64.41%,此时臭氧的产生量为125.21×10^(-6),综合考量在该性能下的协同处理效率最高;在最优低温等离子体性能的条件下,γ-氧化铝载体粒径越小,二甲苯的去除效率越高,协同处理效果最佳,二甲苯总去除率最高可达73.93%,臭氧抑制率最高为66.45%。γ-氧化铝载体对低温等离子体协同处理挥发性有机污染物与臭氧具有一定的促进作用。研究成果可为协同处理挥发性有机污染物提供有效的参考。 展开更多
关键词 兰炭 低温等离子体 挥发性有机污染物 臭氧
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专注晶圆及封测高端设备厂商达仕科技隆重亮相SEMICON CHINA 2023
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《中国集成电路》 2023年第8期90-91,共2页
根据SEMI报告,2022年全球半导体制造设备出货金额相较2021的1026亿美元增长5%,创下1076亿美元的历史新高,中国内地连续第三年成为全球最大的半导体设备市场。今年一季度全球半导体设备出货金额达到268亿美元,比去年同期增长9%,是不可多... 根据SEMI报告,2022年全球半导体制造设备出货金额相较2021的1026亿美元增长5%,创下1076亿美元的历史新高,中国内地连续第三年成为全球最大的半导体设备市场。今年一季度全球半导体设备出货金额达到268亿美元,比去年同期增长9%,是不可多得的亮点。SEMI预计,2024年半导体设备市场会重新恢复增长,预计将以15%的增速重新恢复到1000亿美元以上。 展开更多
关键词 半导体设备 半导体制造设备 高端设备 semi 历史新高
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锡林郭勒褐煤清洁利用技术适用性研究
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作者 史志慧 苏日古嘎 +1 位作者 侯泽健 刘树森 《煤炭加工与综合利用》 CAS 2024年第1期73-78,共6页
锡林郭勒盟褐煤可采储量1 400余亿t,年采量1亿t以上,主要通过燃烧用于发电、供热,利用效率低,高效清洁利用水平有待提高。选择当地3种代表性煤样,以格金低温干馏、热解和直接液化技术为研究手段,讨论不同锡林郭勒褐煤对清洁利用技术的... 锡林郭勒盟褐煤可采储量1 400余亿t,年采量1亿t以上,主要通过燃烧用于发电、供热,利用效率低,高效清洁利用水平有待提高。选择当地3种代表性煤样,以格金低温干馏、热解和直接液化技术为研究手段,讨论不同锡林郭勒褐煤对清洁利用技术的适用性。实验结果表明,3种煤样在不同技术方向上差异显著,结合其气液固三相产物的收率和属性进行评价,认为来自于胜利矿区的样品更适于制取半焦,乌拉盖矿区的样品更适于气化技术,来自于白音华矿区的煤炭则有成为优良直接液化用煤的潜能。结合当地资源环境特点,认为低温热解制取半焦是适宜锡林郭勒褐煤未来清洁利用的技术方向。 展开更多
关键词 锡林郭勒褐煤 格金低温干馏 热解 直接液化 半焦
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Features and Patterns of Primipara Delivery in a Cameroon Semi-Rural Area: The Case of Ayos Locality
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作者 Serge Robert Nyada Cliford E. Ebong +7 位作者 Junie Annick Metogo Ntsama Michelle Mendoua Christiane Nsahlai Véronique Mboua Pascale Mpono Emenguele Isidore Tompeen Etienne Belinga Cyrile Claude Noa Ndoua 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第1期64-73,共10页
Introduction: The delivery of a primipara, a woman giving birth for the first time, is challenging and may lead to complications and influence the obstetrical future of a woman. Materials and Methods: We carried out a... Introduction: The delivery of a primipara, a woman giving birth for the first time, is challenging and may lead to complications and influence the obstetrical future of a woman. Materials and Methods: We carried out a cross-sectional and analytical study at the maternity of the regional hospital annex of Ayos, a semi-rural locality in Cameroon, for the period between January 2012 and December 2020. The objective was to determine the frequency and the determinants of primipara delivery. Results: We recruited 440 cases. The frequency of primipara delivery was 31.8%. The ages of the participants ranged from 12 to 35 years with a mean age of 18.01 ± 3.52 years. Single women contributed to 95.5% of cases while 97.5% were unemployed. The delivery occurred at term in 90.2% and 98.4% of pregnancies were singleton. The delivery was vaginal in 91.6%, while caesarean delivery was done in 8.4% (8% emergency and 0.4% elective). The most frequent maternal complications were genital tract tears (15.7%), post-partum hemorrhage (12.5%) and endometritis (2.7%). The birth weight of newborns ranged from 1070 to 4500 g with a mean of 3024.5 ± 511.4 g. The single marital status, a gestational age between 37 and 42 weeks and a birth weight between 1500 g and 2499 g were significantly associated with vaginal delivery. Conclusion: The frequency of primiparous delivery was relatively high (31.8%) in the Ayos semi-rural health district of Cameroon. Major complications associated with delivery included genital tract tears, post-partum hemorrhage, cesarean section and neo-natal infection. 展开更多
关键词 PRIMIPARA Delivery COMPLICATION semi-Rural Cameroon
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Inequalities for Scalar Curvature and Shape Operator of an R-Lightlike Submanifold in Semi-Riemannian Manifold
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作者 Menedore Karimumuryango Domitien Ndayirukiye +2 位作者 Hans-Fotsing Tetsing Gilbert Nibaruta Aboubacar Nibirantiza 《Journal of Applied Mathematics and Physics》 2023年第7期1895-1913,共19页
We establish the links between the lightlike geometry and basics invariants of the associated semi-Riemannian geometry on r-lightlike submanifold and semi-Riemannian constructed from a semi-Riemannian ambient. Then we... We establish the links between the lightlike geometry and basics invariants of the associated semi-Riemannian geometry on r-lightlike submanifold and semi-Riemannian constructed from a semi-Riemannian ambient. Then we establish some basic inequalities, involving the scalar curvature and shape operator on r-lightlike coisotropic submanifold in semi-Riemannian manifold. Equality cases are also discussed. 展开更多
关键词 semi-Riemannian Submanifold SUBMANIFOLD RIGGING Closed Normalization Associated semi-Riemannian Metric
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中青年缓解期精神分裂症患者社会疏离体验的质性研究 被引量:2
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作者 徐亚南 栗文娟 +3 位作者 赵淑芹 汤语忌 原富强 赵昆朋 《中国全科医学》 北大核心 2024年第9期1088-1094,共7页
背景精神分裂症患者在整个生存期常感知到的较为严重的社会歧视,出现自我疏离或者社会性疏离。目前针对中青年缓解期精神分裂症患者社会疏离方面的研究较少。目的描述中青年缓解期精神分裂症患者社会疏离的体验,旨在为缓解该人群社会疏... 背景精神分裂症患者在整个生存期常感知到的较为严重的社会歧视,出现自我疏离或者社会性疏离。目前针对中青年缓解期精神分裂症患者社会疏离方面的研究较少。目的描述中青年缓解期精神分裂症患者社会疏离的体验,旨在为缓解该人群社会疏离体验制订支持干预方案提供一定的借鉴和参考。方法采用目的抽样法选取18~59岁,曾在新乡医学院第二附属医院住院且出院后愿意继续接受随访的中青年缓解期精神分裂症患者为研究对象,于2022年5—12月通过对受访者进行面对面半结构式深入访谈,并以内容分析法归纳和提炼主题。结果共纳入18名中青年缓解期精神分裂症患者。通过对访谈资料进行分析,共提炼出3个主题和8个亚主题:中青年缓解期精神分裂症患者社会疏离的表现(包括2个亚主题:负性情感体验、期待与行为之间的退缩);中青年缓解期精神分裂症患者社会疏离的主观原因(包括2个亚主题:自我疏离、自我歧视)、中青年缓解期精神分裂症患者社会疏离的客观原因(包括4个亚主题:社会歧视和被动疏离、药物不良反应的影响、精神疾病引起的生活和照护负担加重、缺乏社会支持)。结论中青年缓解期精神分裂症患者由于生理健康受损、心理状况不良、社会支持不足等存在社会疏离,医护人员应加强对该人群的症状管理和心理疏导,政府及社会各界应积极引导对精神疾病的正向认知并给予一定的社会支持;同时强化家庭内部支持,以帮助其重返和适应社会。 展开更多
关键词 精神分裂症 社会疏离 缓解期 中青年 半结构式访谈 质性研究
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