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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability
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作者 Ming-Wei Zhao Zhen-Feng Ma +5 位作者 Cai-Li Dai WeiWu Yong-Quan Sun Xu-Guang Song Yun-Long Cheng Xiang-Yu Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1113-1121,共9页
Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performa... Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications. 展开更多
关键词 Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance
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Magnesium fertilizer application increases peanut growth and pod yield under reduced nitrogen application in southern China
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作者 Yu Gao Ruier Zeng +6 位作者 Suzhe Yao Ying Wang Jianguo Wang Shubo Wan Wei Hu Tingting Chen Lei Zhang 《The Crop Journal》 SCIE CSCD 2024年第3期915-926,共12页
This study investigated the effect of magnesium application on peanut growth and yield under two nitrogen(N)application rates in acidic soil in southern China.The chlorophyll content,net photosynthetic rate and dry ma... This study investigated the effect of magnesium application on peanut growth and yield under two nitrogen(N)application rates in acidic soil in southern China.The chlorophyll content,net photosynthetic rate and dry matter accumulation of the N-sensitive cultivar decreased under reduced N treatments,whereas no effect was observed on the relevant indicators in the N-insensitive variety GH1026.Mg application increased the net photosynthetic rate by increasing the expression of genes involved in chlorophyll synthesis and Rubisco activity in the leaves during the pegging stage under 50%N treatment,while no effect on the net photosynthetic rate was observed under the 100%N treatment.The rate of dry matter accumulation at the early growth stage,total dry matter accumulation and pod yield at harvest increased after Mg application under 50%N treatment by increasing the transportation of assimilates from stems and leaves to pods in both peanut varieties,whereas no effect was found under 100%N treatment.Moreover,Mg application increased the NUE under 50%N treatment.No improvement of NUE in either peanut variety was found under 100%N treatment,while Mg application under the 50%N treatment can obtain a higher economic benefit than the 100%N treatment.In acidic soil,application of 307.5 kg ha^(-1)of Mg sulfate fertilizer under 50%reduced nitrogen application is a suitable fertilizer management measure for improving carbon assimilation,NUE and achieve high peanut yields in southern China. 展开更多
关键词 PEANUT Magnesium YIELD reduced nitrogen application rate
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Empirical Analysis of the Effect of Higher Education on Reducing Crime Rate
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作者 XIAO Pengwen 《International Journal of Technology Management》 2017年第3期61-63,共3页
The theory of pedagogy tells us that the process of the formation of individual moral character is the process of socialization. In social life, especially in the stage of school education of all types and at all leve... The theory of pedagogy tells us that the process of the formation of individual moral character is the process of socialization. In social life, especially in the stage of school education of all types and at all levels, individuals through school education and observational learning, role playing, grasp the moral knowledge, moral conduct and specification, and will them into their own beliefs as well as forming the stable moral consciousness and finally to moral behavior, moral quality can be built up. The criminal psychology school explains the criminal behavior by Freud' s theory of personality structure. Freud said: "I" is the most primitive part of personality, "self" is "my" in the social environment with the development of the "super-me" is the moral of the "self" , it Guide the "self" to limit the "I" psychological impulses. "Super me" is the highest level of personality structure. Under this basis, this paper proposes the empirical analysis on the relationships. In the future, more related research will be finalized. 展开更多
关键词 reducing Crime rate Empirical Analysis Higher Education
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Increased plant density and reduced N rate lead to more grain yield and higher resource utilization in summer maize 被引量:12
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作者 SHI De-yang LI Yan-hong +3 位作者 ZHANG Ji-wang LIU Peng ZHAO Bin DONG Shu-ting 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第11期2515-2528,共14页
Planting at an optimum density and supplying adequate nitrogen(N) to achieve higher yields is a common practice in crop production, especially for maize(Zea mays L.); however, excessive N fertilizer supply in maiz... Planting at an optimum density and supplying adequate nitrogen(N) to achieve higher yields is a common practice in crop production, especially for maize(Zea mays L.); however, excessive N fertilizer supply in maize production results in reduced N use efficiency(NUE) and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index(LAI), intercepted photosynthetically active radiation(IPAR), and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958(ZD958) under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation(DMA), grain yield, NUE, and radiation use efficiency(RUE). However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK(320 kg ha^(–1)) was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m^(–2), compared to LD(5.25 plants m^(–2)), would lead to an optimal balance between yield and resource use efficiency. 展开更多
关键词 summer maize increased plant density reduced N rate N use efficiency resource use efficiency
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Relay-intercropping soybean with maize maintains soil fertility and increases nitrogen recovery efficiency by reducing nitrogen input 被引量:11
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作者 Qing Du Li Zhou +11 位作者 Ping Chen Xiaoming Liu Chun Song Feng Yang Xiaochun Wang Weiguo Liu Xin Sun Junbo Du Jiang Liu Kai Shu Wenyu Yang Taiwen Yong 《The Crop Journal》 SCIE CAS CSCD 2020年第1期140-152,共13页
Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilizat... Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilization can help in dissecting the mechanisms underlying N uptake and utilization in legume-nonlegume intercropping systems.An experiment was performed with three planting patterns:monoculture maize(MM),monoculture soybean(SS),and maize-soybean relay intercropping(IMS),and three N application levels:zero N(NN),reduced N(RN),and conventional N(CN)to investigate crop N uptake and utilization characteristics.N recovery efficiency and 15N recovery rate of crops were higher under RN than under CN,and those under RN were higher under intercropping than under the corresponding monocultures.Compared with MM,IMS showed a lower soil N-dependent rate(SNDR)in 2012.However,the SNDR of MM rapidly declined from 86.8%in 2012 to 49.4%in 2014,whereas that of IMS declined slowly from 75.4%in 2012 to 69.4%in 2014.The interspecific N competition rate(NCRms)was higher under RN than under CN,and increased yearly.Soybean nodule dry weight and nitrogenase activities were respectively 34.2%and 12.5%higher under intercropping than in monoculture at the beginning seed stage.The amount(Ndfa)and ratio(%Ndfa)of soybean N2 fixation were significantly greater under IS than under SS.In conclusion,N fertilizer was more efficiently used under RN than under CN;in particular,the relay intercropping system promoted N fertilizer utilization in comparison with the corresponding monocultures.An intercropping system helps to maintain soil fertility because interspecific N competition promotes biological N fixation by soybean by reducing N input.Thus,a maize-soybean relay intercropping system with reduced N application is sustainable and environmentally friendly. 展开更多
关键词 Maize-soybean relay intercropping reduced nitrogen Biological nitrogen fixation Nitrogen recovery efficiency Soil nitrogen dependent rate
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Decrease of back recombination rate in CdS quantum dots sensitized solar cells using reduced graphene oxide
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作者 Ali Badawi 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期372-377,共6页
The photovoltaic performance of CdS quantum dots sensitized solar cells (QDSSCs) using the 0.2 wt% of reduced graphene oxide and TiO2 nanoparticles (RGO+TiO2 nanocomposite) photoanode is investigated. CdS QDs are... The photovoltaic performance of CdS quantum dots sensitized solar cells (QDSSCs) using the 0.2 wt% of reduced graphene oxide and TiO2 nanoparticles (RGO+TiO2 nanocomposite) photoanode is investigated. CdS QDs are adsorbed onto RGO+TiO2 nanocomposite films by the successive ionic layer adsorption and reaction (SILAR) technique for several cycles. The current density-voltage (J-V) characteristic curves of the assembled QDSSCs are measured at AM1.5 simulated sunlight. The optimal photovoltaic performance for CdS QDSSC was achieved for six SILAR cycles. Solar cells based on the RGO+TiO2 nanocomposite photoanode achieve a 33% increase in conversion efficiency (η) compared with those based on plain TiO2 nanoparticle (NP) photoanodes. The electron back recombination rates decrease significantly for CdS QDSSCs based on RGO+TiO2 nanocomposite photoanodes. The lifetime constant (τ) for CdS QDSSC based on the RGO+TiO2 nanocomposite photoanode is at least one order of magnitude larger than that based on the bare TiO2NPs photoanode. 展开更多
关键词 reduced graphene oxide nanocomposite photoanode back recombination rate quantum dots sensitized solar cell
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Reduced nitrogen application rate with dense planting improves rice grain yield and nitrogen use efficiency: A case study in east China
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作者 Huanhe Wei Tianyao Meng +9 位作者 Jialin Ge Xubin Zhang Tianyi Shi Enhao Ding Yu Lu Xinyue Li Yuan Tao Yinglong Chen Min Li Qigen Dai 《The Crop Journal》 SCIE CSCD 2021年第4期954-961,共8页
Dense planting could be a feasible method for reducing nitrogen(N) application rates without compromising rice grain yield in northeast and central China. It is still unclear whether reduced N application with dense p... Dense planting could be a feasible method for reducing nitrogen(N) application rates without compromising rice grain yield in northeast and central China. It is still unclear whether reduced N application with dense planting(RNDP) can achieve higher rice yield and N use efficiency(NUE) in Jiangsu, east China. Three japonica inbred rice(JI) and three indica hybrid rice(IH) cultivars were grown in a field experiment. Their grain yield, NUE, and related traits were compared under two cultivation treatments:conventional high-yielding practice(CHYP) and RNDP. JI showed similar yields under the two treatments,while IH showed lower yield under RNDP than under CHYP, and the partial factor productivity of N and N use efficiency for grain yield increased(P < 0.05) in both JI and IH under RNDP. Compared with CHYP,RNDP reduced spikelets per panicle but increased panicles per m2 and filled-kernel percentage of JI and IH, and JI's kernel weight was increased(P < 0.05) under RNDP. Shoot biomass weight and nonstructural carbohydrate(NSC) content in the stem at heading and maturity of JI and IH were reduced under RNDP, while harvest index and NSC remobilization reserve were increased(P < 0.05) under RNDP, especially for JI. Our results suggest that RNDP could achieve a higher rice grain yield and NUE, particularly for JI, a dominant rice cultivar type in Jiangsu. For JI, the increased panicles per m2, sink-filling efficiency, harvest index, and NSC remobilization after heading under RNDP contributed to a grain yield similar to that under CHYP. 展开更多
关键词 Japonica inbred rice Grain yield Nitrogen use efficiency reduced nitrogen rate Dense planting
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Determining Optimal Strategies to Reduce Maternal and Child Mortality in Rural Areas in Western China: an Assessment Using the Lives Saved Tool
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作者 JIANG Zhen GUO Sufang +3 位作者 Robert W.SCHERPBIER WEN Chun Mei XU Xiao Chao GUO Yan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期606-610,共5页
China, as a whole, is about to meet the Millennium Development Goals for reducing the maternal mortality ratio (MMR) and infant mortality rate (IMR), but the disparities between rural area and urban area still exists.... China, as a whole, is about to meet the Millennium Development Goals for reducing the maternal mortality ratio (MMR) and infant mortality rate (IMR), but the disparities between rural area and urban area still exists. This study estimated the potential effectiveness of expanding coverage with high impact interventions using the Lives Saved Tool (LiST). It was found that gestational hypertension, antepartum and postpartum hemorrhage, preterm birth, neonatal asphyxia, and neonatal childhood pneumonia and diarrhea are still the major killers of mothers and children in rural area in China. It was estimated that 30% of deaths among 0-59 month old children and 25% of maternal deaths in 2008 could be prevented in 2015 if primary health care intervention coverage expanded to a feasible level. The LiST death cause framework, compared to data from the Maternal and Child Mortality Surveillance System, represents 60%-80% of neonatal deaths, 40%-50% of deaths in 1-59 month old children and 40%-60% of maternal deaths in rural areas of western China. 展开更多
关键词 rate Li an Assessment Using the Lives Saved Tool Determining Optimal Strategies to reduce Maternal and Child Mortality in Rural Areas in Western China
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Synthesis and Performance of an Associative Anti-shear Drag Reducer Based on Hydrogen Bond Association of Dodecyl Methacrylate
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作者 Lu Yong Li Chenhao +5 位作者 Li Hao Chen Yue Xu Dan Wang Yiran Meng Yeqiao Zhang Xiaolai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第1期23-33,共11页
Using K2S2O8-Na2SO3 as the redox initiation system,a hydrogen-bond-association-based dodecyl methacrylate system associative anti-shear drag reducer was synthesised by standard emulsion polymerisation.The reaction pro... Using K2S2O8-Na2SO3 as the redox initiation system,a hydrogen-bond-association-based dodecyl methacrylate system associative anti-shear drag reducer was synthesised by standard emulsion polymerisation.The reaction process was simple and gentle as well as safe and stable.Molecular design was carried out using molecular dynamics simulation methods.The results of infrared spectroscopy,thermogravimetric analysis,differential scanning calorimetry,gel chromatography,and laser light scattering showed that the reaction polymerisation was relatively complete,the product was uniform,the molecular weight distribution was controllable,and the synthesised polymer had good flexibility.The donor lauryl methacrylate-styrene-methacrylic acid(LMA-St-MAA)and acceptor lauryl methacrylate-styrene-dimethylaminoethyl methacrylate(LMA-St-DMA)polymers had an associative intermolecular interaction force,which increased the molecular cluster size of the associative system complex.The complex had good shear resistance,and the test results of the tube pump shear test showed that the synthesised associative oil-soluble polymer drag reduction system exhibited better drag reduction rate performance than poly-α-olefins over repeated cycles.The research results provide a reference plan for minimising the number of station-to-station inputs,thereby ensuring the stability of oil pipelines and reducing transportation costs. 展开更多
关键词 drag reducer associative effect drag reduction rate shear resistance
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糖耐量减低冠心病患者血糖相关指标与SYNTAX评分关系
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作者 宋俊挺 张柱 +2 位作者 韩轩茂 王蒙琴 蔺雪峰 《中国卫生标准管理》 2024年第17期105-108,共4页
目的探讨在急性冠脉综合征并糖耐量减低患者中空腹及口服糖耐量试验(oral glucose tolerance test,OGTT)、糖化血红蛋白与SYNTAX评分(synergy between percutaneous coronary intervention with TAXUS and cardiac surgery)及冠脉病变... 目的探讨在急性冠脉综合征并糖耐量减低患者中空腹及口服糖耐量试验(oral glucose tolerance test,OGTT)、糖化血红蛋白与SYNTAX评分(synergy between percutaneous coronary intervention with TAXUS and cardiac surgery)及冠脉病变支数的相关性。方法回顾性分析2021年9月—2022年10月内蒙古科技大学包头医学院第一附属医院心血管内科住院的45例急性冠脉综合征并糖耐量减低患者,记录患者糖化血红蛋白、OGTT值、冠状动脉造影后SYNTAX评分及冠状动脉病变支数。应用Spearman相关性分析分析OGTT值、糖化血红蛋白与SYNTAX评分及冠脉病变支数的关系。结果OGTT、HbA1c血糖相关指标行正态性分析后示其不服从正态分布,采用Spearman相关性分析示,血糖相关指标与冠状动脉病变评分无明显相关性,SYNTAX评分与冠状动脉病变支数呈正相关(P<0.05)。结论急性冠脉综合征并糖耐量减低患者血糖相关指标与冠状动脉病变评分未见明显相关性,SYNTAX评分与冠状动脉病变支数呈正相关。希望本研究可以为2023年欧洲心脏病学会糖尿病患者心血管疾病管理指南的更新提供参考。 展开更多
关键词 急性冠脉综合征 糖耐量减低 糖化血红蛋白 冠脉病变 评分 相关性
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无缝钢管张力减径工艺减径率分配修正模型理论研究
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作者 胡建华 郝亚栋 +4 位作者 黄宇龙 双远华 李靖 马家旺 陈建勋 《钢管》 CAS 2024年第3期42-48,共7页
无缝钢管张力减径工艺减径率分配是孔型分配合理与否的关键步骤,但其分配仍依赖于经验公式。从金属流动的角度分析了减径率的分配规律,在经验的基础上提出了“三点两段统合式”减径率分配修正模型。将修正模型得到的结果与传统模型计算... 无缝钢管张力减径工艺减径率分配是孔型分配合理与否的关键步骤,但其分配仍依赖于经验公式。从金属流动的角度分析了减径率的分配规律,在经验的基础上提出了“三点两段统合式”减径率分配修正模型。将修正模型得到的结果与传统模型计算结果以及企业生产数据相比,发现变化趋势相近,减径率和减径量变化曲线更加光滑,应用于生产有利于金属流动。 展开更多
关键词 无缝钢管 张力减径 减径率 三点两段统合式 修正模型 金属流动
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不同施氮量下玉米生长及产量对间作豆科绿肥的响应
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作者 董勇杰 张刁亮 +5 位作者 李越 彭建辰 胡发龙 殷文 柴强 樊志龙 《中国农业科学》 CAS CSCD 北大核心 2024年第10期1900-1914,共15页
【目的】明确不同施氮量下玉米生长及产量对间作豆科绿肥的响应,为构建干旱灌区基于绿肥的玉米氮肥节约型生产模式提供依据。【方法】采用裂区试验设计,主区设玉米间作箭筈豌豆(M||V)和单作玉米(SM)2种种植模式,副区设5个施氮水平:地方... 【目的】明确不同施氮量下玉米生长及产量对间作豆科绿肥的响应,为构建干旱灌区基于绿肥的玉米氮肥节约型生产模式提供依据。【方法】采用裂区试验设计,主区设玉米间作箭筈豌豆(M||V)和单作玉米(SM)2种种植模式,副区设5个施氮水平:地方推荐施氮量N360(360 kg·hm^(-2))、减量25%施氮N270(270 kg·hm^(-2))、减量50%施氮N180(180 kg·hm^(-2))、减量75%施氮N90(90 kg·hm^(-2))、不施氮N0。对玉米叶面积指数(LAI)、叶日积(LAD)、光能利用率、干物质积累量及产量进行了相关研究。【结果】间作绿肥能够提高减量施氮(N270、N180、N90、N0)条件下玉米出苗后75—150 d的LAI,并增加其全生育期LAD和光能利用率。在N270、N180、N90、N0下,M||V较SM玉米75—150 d LAI、全生育期总LAD、光能利用率平均显著提高了9.8%、8.2%、4.6%。在M||V中,N270与N360的玉米出苗后75—150 d LAI、全生育期总LAD、光能利用率之间没有显著差异,而显著高于其他施氮水平;在SM中,玉米出苗后75—150 d的LAI、全生育期总LAD、光能利用率随施氮量的减少而降低。间作绿肥显著提高了N270、N180、N90、N0条件下玉米出苗后90—150 d的干物质积累量,在同一氮肥减量条件(N270、N180、N90、N0)下,M||V较SM的玉米干物质积累量平均显著提高了4.6%。在玉米出苗后75—130 d,M||V较SM的玉米群体生长率显著提高了5.9%。M||V较同一减量施氮(N270、N180、N90、N0)条件下的SM玉米籽粒产量平均显著提高了8.5%。在M||V中,N270的籽粒产量显著高于N360。M||V较SM玉米穗粒数和千粒重分别平均显著提高6.0%和6.3%。拟合曲线结果表明,间作绿肥可以使玉米在施氮量261.4 kg·hm^(-2)时获得最高产量14876.4 kg·hm^(-2),而单作玉米获得最高产量14012.5 kg·hm^(-2)时的最佳施氮量为348.6 kg·hm^(-2)。减量施氮对绿肥鲜草产量和绿肥氮素积累量的影响显著,M||V N270较M||V N360、M||V N90、M||V N0的绿肥鲜草产量分别显著高了3.8%、4.6%、9.7%,较M||VN90和M||VN0之间的绿肥氮素积累量显著高了5.3%和11.9%。间作绿肥主要通过提高玉米的干物质积累总量,进而增加减量施氮条件下玉米的穗粒数和千粒重,从而使间作玉米在氮肥减量下能够获得较高水平的籽粒产量。【结论】间作豆科绿肥可使氮肥减量25%的玉米获得高于地方推荐施氮量单作玉米的产量水平,可作为试区以及相似生态区域玉米化学氮肥减量的推荐生产模式。 展开更多
关键词 间作绿肥 减量施氮 产量 光能利用率 玉米 箭筈豌豆
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还原介质对镍渣直接还原提铁的影响
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作者 郑江华 宗红星 +3 位作者 李彬 任学根 申莹莹 杜雪岩 《烧结球团》 北大核心 2024年第5期96-102,共7页
如何从富铁镍渣中高效提铁是该资源综合再利用的关键。本文采用焦炭和烟煤作为还原剂,对镍渣进行直接还原提铁试验研究,对比两种还原剂在镍渣还原过程中产生有效还原介质的差异,借助热力学软件对不同还原介质的还原能力进行热力学分析,... 如何从富铁镍渣中高效提铁是该资源综合再利用的关键。本文采用焦炭和烟煤作为还原剂,对镍渣进行直接还原提铁试验研究,对比两种还原剂在镍渣还原过程中产生有效还原介质的差异,借助热力学软件对不同还原介质的还原能力进行热力学分析,然后通过试验及表征研究两种还原剂对镍渣还原过程金属化率变化及微观结构演变的影响。结果表明:烟煤含有的高挥发分会产生CO-H_(2)混合的还原介质,而焦炭则主要以CO还原介质为主;热力学分析结果表明,CO-H_(2)混合气对铁氧化物的还原能力优于纯CO。镍渣还原焙烧试验结果显示,使用烟煤作为还原剂,1 300℃下还原20 min,镍渣球团的金属化率可达90.20%;而采用焦炭作为还原剂时其金属化率仅达到72.97%,烟煤对镍渣的还原能力优于焦炭。 展开更多
关键词 镍渣 还原介质 金属化率 微观结构
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减氧空气驱集输管道抗氧缓蚀剂优选与评价
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作者 於亮 薛琨 +4 位作者 李晓燕 史宝成 伍丽娟 刘凯 张兴凯 《石油机械》 北大核心 2024年第9期139-146,共8页
目前抗氧缓蚀剂存在种类稀少、单一种类缓蚀剂的性能不够好以及经济成本较高等一系列问题。为此,结合国内某减氧空气驱集输管道实际工况特点,通过对氧腐蚀机理研究,选取了3种现已研发的油田常用抗氧缓蚀剂EQI、HTT和TCT,对其进行了动态... 目前抗氧缓蚀剂存在种类稀少、单一种类缓蚀剂的性能不够好以及经济成本较高等一系列问题。为此,结合国内某减氧空气驱集输管道实际工况特点,通过对氧腐蚀机理研究,选取了3种现已研发的油田常用抗氧缓蚀剂EQI、HTT和TCT,对其进行了动态腐蚀评价试验和表面形貌分析,通过分子动力学模拟其在Fe表面的吸附情况,得到缓蚀剂分子在水溶液环境下对Fe基体表面的吸附能大小,结合对比分析模拟和试验的结果,筛选出缓蚀性能最佳的缓蚀剂。试验和模拟结果均表明:水溶液中3种缓蚀剂分子在Fe基体表面的吸附能大小从高到低依次为TCT>EQI>HTT,缓蚀剂分子吸附能越大,缓蚀性能越佳。所得结论可为减氧空气驱集输系统的腐蚀防护工作提供理论指导。 展开更多
关键词 集输管道 减氧空气驱 抗氧缓蚀剂 分子动力学模拟 缓蚀速率 氧腐蚀
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消泡剂与减缩剂对聚合物改性水泥砂浆干燥收缩和质量损失的影响 被引量:1
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作者 安艳菲 范树景 杭法付 《新型建筑材料》 2024年第2期83-86,91,共5页
研究了单掺消泡剂、单掺减缩剂及二者复掺对聚合物改性水泥砂浆的干燥收缩率和质量损失率的影响。结果表明,单掺消泡剂时,砂浆的干燥收缩率与质量损失率均会降低,且降低幅度与掺量成正比;单掺减缩剂时,砂浆的干燥收缩率降低且降幅与掺... 研究了单掺消泡剂、单掺减缩剂及二者复掺对聚合物改性水泥砂浆的干燥收缩率和质量损失率的影响。结果表明,单掺消泡剂时,砂浆的干燥收缩率与质量损失率均会降低,且降低幅度与掺量成正比;单掺减缩剂时,砂浆的干燥收缩率降低且降幅与掺量成正比,质量损失率整体降低,但随着掺量的增加,减缩剂对质量损失的抑制作用逐渐降低;二者复掺对砂浆的干燥收缩与质量损失的抑制作用大于各自单掺时,具有明显的协同效应。砂浆的质量损失率与干燥收缩率之间存在幂函数关系,曲线参数受外加剂种类及掺量影响。 展开更多
关键词 聚合物改性水泥砂浆 消泡剂 减缩剂 干燥收缩率 质量损失率
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中国XRT智能预选抛废技术应用研究与实践
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作者 罗主平 刘建华 +5 位作者 孙业长 杨婷 杨璐 阳建国 张文国 周承丞 《金属矿山》 CAS 北大核心 2024年第8期79-92,共14页
我国矿石资源普遍禀赋差,选矿成本高,但选矿工艺技术及设备研发水平较高。为了推动近年取得重大突破的高效大块预选设备———XRT智能选矿机更好地服务矿山,提升矿山的生产力水平和经济效益,建设绿色生态矿山,在简要介绍了XRT智能选矿... 我国矿石资源普遍禀赋差,选矿成本高,但选矿工艺技术及设备研发水平较高。为了推动近年取得重大突破的高效大块预选设备———XRT智能选矿机更好地服务矿山,提升矿山的生产力水平和经济效益,建设绿色生态矿山,在简要介绍了XRT智能选矿机系统组成与分选原理、工艺技术的适用性及要求、工艺技术与设备的特点和优越性基础上,按矿种分类介绍了代表性矿山开展XRT智能预选抛废研究与生产实践的情况。试验研究与生产实践表明:XRT智能选矿机对矿种具有广泛的适应性,且具有分选客观、科学、精准、智能、节能、环保等特点;可以兼顾两种及以上目标矿物或元素的高效综合回收;应用工艺简单,对现场碎矿流程的冲击、干扰小;入选粒度粗,高度契合能抛早抛、能收早收理念;对薄、小、边、残、贫矿石资源的开发具有显著的扩能、降本、提质意义。并就XRT智能选矿机的研发和工艺技术应用给出了7点建议:解决分选粒度向上下拓展与分选效率、可靠性、稳定性和工艺的适应性问题,以实现多抛多收的目标;解决设备的大型化、系列化问题,以降低投资和生产成本,并方便现场配置和生产管理;研发三产品XRT智能选矿机,为后续制定高效的选矿工艺和产品方案创造条件;制定全面、科学的矿废判定标准,以实现资源效益的最大化;支持并携手矿石选择性破碎技术共同发展,为预选创造更好的条件;科学制定包容其他预选抛废技术的高效抛废工艺,使抛废更彻底、工艺流程更简洁顺畅、技术经济指标更好;论证废石洗矿工艺替代筛分洗矿工艺或给矿洗矿工艺的科学性,以使全系统工艺流程更简单、生产环境更整洁、投资和生产成本更低。最后指出,除磁铁矿石外,其他铁矿石及非金属矿石的粗粒预选抛废,应用不断进步的XRT智能预选抛废技术应是大势所趋。 展开更多
关键词 XRT 智能选矿机 废石混入率 早抛多抛 早收多收 综合利用 降本增效提质 绿色矿山
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“双碳”目标下石油炼制技术研发策略与工业实践 被引量:1
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作者 许友好 李浩天 刘昌呈 《石油炼制与化工》 CAS CSCD 北大核心 2024年第1期171-179,共9页
百年石油炼制行业面临着“双碳”目标和第三次能源转型带来的燃料需求量持续减少的双重挑战,而传统石油炼制技术追求高转化率,造成石油资源碳氢利用效率低,CO_(2)排放高,与“减排增效”的转型发展目标相悖。为此,基于石油分子管理理念,... 百年石油炼制行业面临着“双碳”目标和第三次能源转型带来的燃料需求量持续减少的双重挑战,而传统石油炼制技术追求高转化率,造成石油资源碳氢利用效率低,CO_(2)排放高,与“减排增效”的转型发展目标相悖。为此,基于石油分子管理理念,以产品高选择性为石油炼制技术研发策略,开发出变革性的小分子烷烃加工、重油加工和低碳烯烃生产技术并进行工业实践,实现源头降碳和过程降碳,满足石油炼制行业向绿色低碳、减油增化、清洁生产方向转型日益迫切的需求。 展开更多
关键词 碳达峰 碳中和 石油炼制 转化率 选择性 绿色低碳 减油增化 清洁生产
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小麦胚芽肽和大豆酶解蛋白的体外抗氧化活性研究
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作者 边智尧 陈宝江 +2 位作者 申帅峰 随腾玖 韩帅娟 《饲料工业》 CAS 北大核心 2024年第7期80-86,共7页
试验旨在研究小麦胚芽肽和大豆酶解蛋白的分子质量分布和体外抗氧化活性。试验采用单因素完全随机设计,以维生素C为对照,分别测定小麦胚芽肽和大豆酶解蛋白在0.625、1.25、2.5、5、10 mg/mL浓度下对DPPH自由基、羟自由基和2,2-联氮-二(3... 试验旨在研究小麦胚芽肽和大豆酶解蛋白的分子质量分布和体外抗氧化活性。试验采用单因素完全随机设计,以维生素C为对照,分别测定小麦胚芽肽和大豆酶解蛋白在0.625、1.25、2.5、5、10 mg/mL浓度下对DPPH自由基、羟自由基和2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基的清除率,并通过测定T-AOC吸光度值计算总还原力。结果表明:使用高效液相色谱测定小麦胚芽肽和大豆酶解蛋白重均分子质量分别为513 u和551 u,二者分子质量小于1000 u的比例分别为90.22%和86.93%。在一定浓度范围内,随小麦胚芽肽和大豆酶解蛋白浓度的升高,其体外抗氧化性能线性增加(P<0.05),且呈正相关关系。在10 mg/mL浓度时,小麦胚芽肽对DPPH自由基、羟自由基和ABTS自由基清除率和总还原力分别为90.39%、70.66%、96.24%和2.23,大豆酶解蛋白对DPPH自由基、羟自由基和ABTS自由基清除率和总还原力分别达到65.55%、68.21%、75.14%和0.51。综上,在本试验条件下,不同浓度小麦胚芽肽和大豆酶解蛋白均具有一定的抗氧化能力,且小麦胚芽肽相较于大豆酶解蛋白的抗氧化能力更强。 展开更多
关键词 小麦胚芽肽 大豆酶解蛋白 体外抗氧化性能 总还原力 自由基清除率
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膨润土种类及黄原胶含量对减阻泥浆性能的影响
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作者 高增奎 张睿钦 +2 位作者 王先甲 胡家新 王丹生 《土木工程与管理学报》 2024年第1期19-24,共6页
减阻触变泥浆在地下综合管廊顶管施工中具有支撑、填充、润滑等重要作用。本文对减阻触变泥浆中主要原材料—膨润土的种类及含量对泥浆性能的影响进行了实验研究。结果表明:减阻泥浆的漏斗粘度、失水量和析水率等性能指标随钠基、有机... 减阻触变泥浆在地下综合管廊顶管施工中具有支撑、填充、润滑等重要作用。本文对减阻触变泥浆中主要原材料—膨润土的种类及含量对泥浆性能的影响进行了实验研究。结果表明:减阻泥浆的漏斗粘度、失水量和析水率等性能指标随钠基、有机和钙基3种膨润土含量的变化规律基本相同。由钠基或有机膨润土配制的泥浆失水量性能优于钙基膨润土,但钙基膨润土在泥浆漏斗粘度性能上表现更好;由上述3种类型膨润土分别配制的泥浆析水率性能相当。另外,本文还研究了黄原胶含量对减阻泥浆性能的影响,实验结果表明添加黄原胶能显著降低减阻触变泥浆的失水量,并在一定程度上提高泥浆的漏斗粘度。 展开更多
关键词 顶管施工 减阻触变泥浆 膨润土种类 黄原胶 漏斗粘度 失水量 析水率
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改性TiO_(2)-太阳光协同强化秸秆产糖的研究
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作者 相玉琳 张永博 +1 位作者 吴警旗 张旭帆 《榆林学院学报》 2024年第2期1-5,共5页
为了强化生物质能源的清洁利用,提高生物质糖转化率,合成了L-缬氨酸改性二氧化钛复合催化剂;随后以稻草秸秆为原料,木质素去除率与还原糖产量为目标,通过改性二氧化钛-太阳光协同预处理强化秸秆酶解糖化效率。过程中考察了催化剂种类、... 为了强化生物质能源的清洁利用,提高生物质糖转化率,合成了L-缬氨酸改性二氧化钛复合催化剂;随后以稻草秸秆为原料,木质素去除率与还原糖产量为目标,通过改性二氧化钛-太阳光协同预处理强化秸秆酶解糖化效率。过程中考察了催化剂种类、浓度、pH、太阳光光照时间以及光照方式对秸秆还原糖转化率的影响。在单因素试验基础上,对工艺参数进行了正交试验优化。SEM与FT-IR分析结果显示,L-缬氨酸成功负载于二氧化钛颗粒上;形成的复合催化剂联合太阳光辐照可有效强化秸秆还原糖转化率。综合考虑经济性因素,最终方案选择催化剂浓度为35 mg/L、pH为6.0、预处理时间70 min。验证试验显示,木质素去除率可达93.1%。预处理后,酶解糖化过程采用光暗交替循环方案,酶载量20 FPU/g,其还原糖转化率可达117.3 mg/g,还原糖转化率非常显著。 展开更多
关键词 改性二氧化钛 秸秆 太阳光 木质素去除率 还原糖得率
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