期刊文献+
共找到14,032篇文章
< 1 2 250 >
每页显示 20 50 100
A Biogas Production Model from the Combination of Pig Manure and Cow Dung in N’Zérékoré City, Republic of Guine
1
作者 Madeleine Kamano Oumar Keita +1 位作者 Ansoumane Sakouvogui Aboubacar Sangare 《Energy and Power Engineering》 2024年第9期293-312,共20页
This present research work focuses on the valorization of pig droppings for production of biogas in mono digestion and co-digestion with proportions of cow dung from the urban commune of N’Zérékoré. It... This present research work focuses on the valorization of pig droppings for production of biogas in mono digestion and co-digestion with proportions of cow dung from the urban commune of N’Zérékoré. It was carried out in December 2020 in the Physics laboratory of the University of N’Zérékoré. The anaerobic digestion process took 25 days in an almost constant ambient temperature of 25˚C. Five digesters were loaded on 12/06/2020, two of which with 1 kg of pig dung and 1 kg of cow dung both in mono-digestion. The 3 other digesters in co-digestion with different proportions of pig manure and cow dung. The substrate in each digester is diluted in 2 liters of water, with a proportion of (1/2). The main results obtained are: 1) the evolution of the temperature and pH during digestion process, 2) the average biogas productions 0.61 liters for (D1);1.20 liter for (D2);1.65 liter for (D3);1.51 liter for (D4) and 1.31 liter for (D5). The cumulative amounts of biogas are respectively: D1 (7.95 liters), D2 (15.60 liters), D3 (21.50 liters), D4 (19.65 liters) and D5 (17.05 liters). The total cumulative production is 81.75 liters at the end of the process. The originality of this research work is that the proposed model examines the relation between the daily biogas production and the variation of temperature, pH and pressure. The combustibility test showed the biogas produced during the first week was no combustible (contains less than 50% methane). Combustion started from the biogas produced from the 15th day and it is from the 20th day that a significant amount of stable yellow/blue flame was observed. The results of this study show the combination of pig manure and cow dung presents advantages for optimal biogas production. 展开更多
关键词 production Experimental MOdEL Pig Manure Cow dung BIOGAS N’Zérékoré republic of Guinea
下载PDF
政府R&D补贴的技术创新效应分析--基于2009-2021年中国的经验数据
2
作者 臧传琴 《山东商业职业技术学院学报》 2024年第4期1-8,共8页
政府R&D补贴既可以通过提供公共服务的方式直接作用于技术创新,也可以通过对社会资本的引导作用间接影响技术创新,其总效应取决于两种影响的方向与大小。基于2009—2021年中国的经验数据,建立了由技术创新方程和引致方程共同组成的... 政府R&D补贴既可以通过提供公共服务的方式直接作用于技术创新,也可以通过对社会资本的引导作用间接影响技术创新,其总效应取决于两种影响的方向与大小。基于2009—2021年中国的经验数据,建立了由技术创新方程和引致方程共同组成的动态模型,对政府R&D补贴的技术创新效应进行了实证分析。结果发现:持续增加的政府R&D补贴带来了国内专利授权数量的稳定增加,技术创新效应较为显著;政府R&D补贴不仅对技术创新产生了积极的直接影响,也通过引导社会资本投资于研发领域而对技术创新产生了积极的间接影响;政府R&D补贴的技术创新效应存在区域差异,中东部地区为正,而西部地区为负。提高资金使用效率、积极引导社会资本投资技术研发、努力改善欠发达地区的研发环境,无疑是提高政府R&D补贴技术创新效应的必要选择。 展开更多
关键词 r&d补贴 技术创新 直接效应 间接效应
下载PDF
Study on Sonneratia apetala productivity in restored forests in Leizhou Peninsula, China 被引量:1
3
作者 韩维栋 高秀梅 Edwin Teunissen 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期229-234,276,共7页
The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage... The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China. 展开更多
关键词 Sonneratia apetala MANGrOVE Biomass Leizhou Peninsula Study on Sonneratia apetala productivity in restored forests in Leizhou Peninsula China HAN Wei-dong GAO Xiu-mei (Zhanjiang Ocean University Zhanjiang 524088 Guangdong P.r. China)
下载PDF
云南省R&D经费投入结构动态研究 被引量:1
4
作者 张和平 钟翔 +1 位作者 段江涛 贺新华 《中国科技资源导刊》 2024年第1期92-99,共8页
为研究云南省“十二五”以来R&D经费投入结构变化,分析R&D经费投入现状,并与全国,东、中、西部地区及临近省份进行了对比;从资金来源和资金配置视角,运用Cobb-Douglas效用函数及其修正模型对R&D经费投入结构展开动态分析。... 为研究云南省“十二五”以来R&D经费投入结构变化,分析R&D经费投入现状,并与全国,东、中、西部地区及临近省份进行了对比;从资金来源和资金配置视角,运用Cobb-Douglas效用函数及其修正模型对R&D经费投入结构展开动态分析。结果表明:云南省R&D经费投入结构不尽合理,资金来源中政府资金占比较低且呈下降趋势,资金配置中基础研究和应用研究投入不足,与最优结构偏离程度较大。针对存在的问题,提出持续加大政府R&D经费投入力度、围绕产业链提升基础研究和应用研究比重的建议。 展开更多
关键词 r&d经费 政府r&d投入 资源配置 活动类型 云南省 Cobb-douglas效用函数
下载PDF
R&D资本化背景下我国TFP增长率再测算 被引量:1
5
作者 杜瑶 许永洪 《统计研究》 CSSCI 北大核心 2024年第1期33-45,共13页
研究与试验发展(R&D)资本对经济增长和科技创新作用日益凸显,但对于R&D资本的核算亟待完善。本文基于SNA2008和CSNA2016框架,将R&D支出作为资本形成,对我国各省份物质资本存量和R&D资本存量进行规范化测算,使用随机前... 研究与试验发展(R&D)资本对经济增长和科技创新作用日益凸显,但对于R&D资本的核算亟待完善。本文基于SNA2008和CSNA2016框架,将R&D支出作为资本形成,对我国各省份物质资本存量和R&D资本存量进行规范化测算,使用随机前沿分析法重新估算1991—2019年间的全要素生产率(TFP)增长率。研究发现:第一,我国R&D资本存量规模呈总体递增和地区聚集趋势;第二,1991—2019年间,我国广义TFP增长率年平均增幅为2.10%,对经济增长存在正向作用;第三,将TFP增长率分解为技术进步、前沿技术效率和规模效应,发现技术进步对TFP增长率的贡献最大,是推动我国TFP增长的主导力量,但却呈现逐年递减的趋势;第四,随着我国对R&D投入的不断增加与重视,R&D对我国广义TFP增长率的贡献呈现递增的趋势,R&D的贡献逐渐成为推动我国科技进步的主要力量。 展开更多
关键词 r&d资本化 r&d资本存量 TFP增长率 随机前沿分析
下载PDF
政府R&D资助对OFDI逆向绿色创新的影响机制研究 被引量:1
6
作者 韩先锋 刘娟 李勃昕 《运筹与管理》 CSSCI CSCD 北大核心 2024年第1期158-164,共7页
应用中国分省区层面数据并采用面板门槛模型,实证考察了政府R&D资助影响OFDI逆向绿色创新的动态效应。研究发现,OFDI对国内绿色创新产生了显著的驱动效应,但这种影响呈现出明显的先负后正的“U”型动态演化特征;政府R&D资助会... 应用中国分省区层面数据并采用面板门槛模型,实证考察了政府R&D资助影响OFDI逆向绿色创新的动态效应。研究发现,OFDI对国内绿色创新产生了显著的驱动效应,但这种影响呈现出明显的先负后正的“U”型动态演化特征;政府R&D资助会正向调节OFDI逆向绿色创新溢出,且存在最适宜于OFDI逆向绿色创新的政府R&D资助区间(0.366,0.428],过高或过低强度的政府R&D资助均会在一定程度上造成OFDI逆向绿色创新的红利损失;政府R&D资助调节下OFDI对绿色创新的动态影响具有显著时空异质性,即在时空维度上存在“激励效应”与“挤出效应”交替演化的鲜明特征。 展开更多
关键词 政府r&d资助 对外直接投资 绿色创新
下载PDF
Calcium-fortified fresh milk ameliorates postmenopausal osteoporosis via regulation of bone metabolism and gut microbiota in ovariectomized rats 被引量:1
7
作者 Qishan Wang Bin Liu +5 位作者 Xianping Li Junying Zhao Zongshen Zhang Weicang Qiao Xinyue Wei Lijun Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1258-1270,共13页
The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorat... The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorating postmenopausal osteoporosis in a rat model established using bilateral ovariectomy.After 3 months of FM(containing vitamin D,and casein phosphopeptides,1000 mg Ca/100 g)or control milk(110 mg Ca/100 g milk)supplementation,bone changes were assessed using dual-energy X-ray absorptiometry,microcomputed tomography,and bone biomechanical testing.The results revealed that FM can regulate bone metabolism and gut microbiota composition,which act on bone metabolism through pathways associated with steroid hormone biosynthesis,relaxin signaling,serotonergic synapse,and unsaturated fatty acid biosynthesis.Furthermore,FM administration significantly increased bone mineral content and density in the lumbar spine and femur,as well as femoral compressive strength,while improving femoral trabecular bone parameters and microarchitecture.Mechanistically,we found that the effects may be due to increased levels of estrogen,bone formation marker osteocalcin,and procollagen typeⅠN-propeptide,and decreased expression of the bone resorption marker C-telopiptide and tartrate-resistant acid phosphatase 5b.Overall,the findings suggest that FM is a potential alternative therapeutic option for ameliorating postmenopausal osteoporosis. 展开更多
关键词 dairy products CALCIUM Vitamin d Bone turnover markers Gut microbiota Postmenopausal osteoporosis
下载PDF
F_(m)、P_(n)⊙F_(m)和C_(n)⊙F_(m)的r-hued染色研究
8
作者 西日尼阿依·努尔麦麦提 刘凤霞 《四川师范大学学报(自然科学版)》 CAS 2024年第2期269-274,共6页
给定2个图G和H,它们的corona乘积图记为G⊙H,是将图G拷贝一份、图H拷贝|V(G)|份,图G的第i个顶点和图H的第i个拷贝份的每个顶点连边而得到的图.图G的(k,r)-染色是图G正常k-染色,使得度数为d的每个顶点的邻点至少染min{d,r}种不同的颜色.r... 给定2个图G和H,它们的corona乘积图记为G⊙H,是将图G拷贝一份、图H拷贝|V(G)|份,图G的第i个顶点和图H的第i个拷贝份的每个顶点连边而得到的图.图G的(k,r)-染色是图G正常k-染色,使得度数为d的每个顶点的邻点至少染min{d,r}种不同的颜色.r-hued染色数是最小正整数k,使得图G具有(k,r)-染色,用χr(G)来表示.主要讨论F_(m),P_(n)⊙F_(m)和C_(n)⊙F_(m)的r-hued染色数. 展开更多
关键词 (k r)-染色 r-hued色数 corona乘积图
下载PDF
广东省R&D资本存量的测度、生产效率与政策效应
9
作者 杨新洪 《深圳社会科学》 2024年第5期69-81,共13页
本文研究目的是计算广东省R&D资本存量,探讨R&D资本化对GDP的影响,并以此考察工业企业R&D生产效率的影响因素及相关政策效果。采用2010—2020年广东省及21个地市工业企业面板数据,使用永续盘存法测算广东省及21个地市的R&am... 本文研究目的是计算广东省R&D资本存量,探讨R&D资本化对GDP的影响,并以此考察工业企业R&D生产效率的影响因素及相关政策效果。采用2010—2020年广东省及21个地市工业企业面板数据,使用永续盘存法测算广东省及21个地市的R&D资本存量,并使用R&D强度,更好地反映了R&D投入状况。在计算R&D资本存量的基础上,构建柯布-道格拉斯知识生产函数模型进行分析,发现R&D资本存量和研发人员投入对R&D产出具有显著正效应,但研发人员产出弹性远高于资本存量,其中全时非全时工作人员比对新产品销售收入也具有显著正效应。企业规模、高薪技术企业减免税对R&D产出均具有显著正效应,但国有产权增加会导致R&D产出的下降,另外,境外技术引进仅对新产品销售收入具有显著正效应。最后,使用DID模型和平行趋势检验进行广东省内21个地市的政策评估,发现政策实施四年后对R&D劳动投入出现显著负效应,说明政策实施导致企业R&D劳动力投入下降,对广东省“十二五”后相关地市R&D政策效应评估为广东省未来R&D政策的制定提供了重要参考。根据研究结果,提出以下政策建议:在政策的设定上,应设定更合理的高薪企业认定标准,并考虑企业可能存在的欺骗空间,确保政策资金的扶持更为合理地流动;在R&D政策制定上,应更多刺激民营经济的科技创新活力,加快形成新质生产力。同时,应充分发挥R&D政策的示范引领效应,促进企业更新升级。 展开更多
关键词 新质生产力 r&d资本存量 GdP影响度测算 知识生产函数 dId模型 生产 效率 政策效应 高质量发展
下载PDF
血清D-二聚体和sRAGE水平对老年冠心病患者介入治疗后短期不良预后的预测价值 被引量:4
10
作者 单华静 黄能为 《中国动脉硬化杂志》 CAS 2024年第1期57-64,共8页
[目的]探究D-二聚体和可溶性晚期糖基化终末产物受体(sRAGE)水平对老年冠心病患者经皮冠状动脉介入治疗(PCI)后短期不良预后的预测价值。[方法]收集2019年4月-2020年6月在黄冈市中心医院首次诊断为冠心病的316例老年患者的临床资料,根... [目的]探究D-二聚体和可溶性晚期糖基化终末产物受体(sRAGE)水平对老年冠心病患者经皮冠状动脉介入治疗(PCI)后短期不良预后的预测价值。[方法]收集2019年4月-2020年6月在黄冈市中心医院首次诊断为冠心病的316例老年患者的临床资料,根据随访期间患者是否发生主要不良心血管事件(MACE)将其分为MACE组(n=52)和非MACE组(n=264),采用单因素分析和多因素Logistic回归分析患者术后发生MACE的独立影响因素,依据患者预后的独立影响因素建立列线图预测模型并进行验证。通过曲线拟合和阈值效应分析确定D-二聚体和sRAGE水平的阈值效应,并通过Kaplan-Meier曲线评估D-二聚体和sRAGE水平对MACE发生的影响。[结果]术后一年期间,纳入的316例老年冠心病患者中有52例(16.46%)发生MACE。MACE组患者的体质指数(BMI)、高血压占比、糖尿病占比、GRACE评分、支架数目、载脂蛋白(Apo)B、ApoB/ApoA、低密度脂蛋白胆固醇(LDLC)、脂蛋白(a)[Lp(a)]以及D-二聚体水平均高于非MACE组,sRAGE水平低于非MACE组,差异均具有统计学意义(P<0.05)。多因素Logistic回归分析表明,高GRACE评分、高Lp(a)及高D-二聚体水平为老年冠心病患者PCI术后发生MACE的独立危险因素,高sRAGE水平为保护因素(P<0.05)。曲线拟合发现,随着D-二聚体水平的升高以及sRAGE水平的降低,患者术后发生MACE的概率呈上升趋势。Kaplan-Meier曲线显示,较高D-二聚体水平的患者MACE的发生概率显著高于低D-二聚体水平的患者(P<0.001),较低sRAGE水平的患者MACE的发生概率显著高于高sRAGE水平的患者(P<0.001)。依据预后独立影响因素构建列线图模型,其一致性指数为0.796(95%CI:0.723~0.834),ROC曲线AUC为0.851(95%CI:0.806~0.892),具有较好的区分度。[结论]高D-二聚体及低sRAGE水平是老年冠心病患者PCI术后发生MACE的重要危险因素,且对术后短期不良预后具有较高的预测价值。 展开更多
关键词 d-二聚体 晚期糖基化终末产物受体 介入治疗 冠心病 不良预后 预测价值
下载PDF
企业R&D支出费用化资本化与会计盈余管理行为选择研究——基于中国部分上市公司的经验数据
11
作者 姚慧娴 徐荣 《安徽工程大学学报》 CAS 2024年第4期73-81,共9页
本文基于中国部分上市公司的数据,选取R&D支出全部费用化、全部资本化、部分资本化3个虚拟变量及R&D支出费用化金额、资本化金额用以表征R&D支出披露形式,研究上市公司R&D支出会计政策选择是否与盈余管理程度相关,进而... 本文基于中国部分上市公司的数据,选取R&D支出全部费用化、全部资本化、部分资本化3个虚拟变量及R&D支出费用化金额、资本化金额用以表征R&D支出披露形式,研究上市公司R&D支出会计政策选择是否与盈余管理程度相关,进而检验R&D支出会计处理盈余管理路径,即检验R&D支出费用化、资本化的确定依据是否受其他非准则因素影响。研究结果显示,有条件资本化会计处理可能成为管理层盈余管理手段,包括应计盈余管理和真实盈余管理。在确定R&D支出费用化金额、资本化金额及R&D支出费用化强度上,管理层除了依据会计准则,还要依据当期利润情况、所得税负、利润质量、审计成本、利润平滑和公司独立性的影响。 展开更多
关键词 r&d支出 应计盈余管理 真实盈余管理 利润平滑
下载PDF
Two-dimensional ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes for enhanced photocatalytic water splitting hydrogen production 被引量:7
12
作者 Wei Ou Jiaqi Pan +7 位作者 Yanyan Liu Shi Li Hongli Li Weijie Zhao Jingjing Wang Changsheng Song Yingying Zheng Chaorong Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第4期188-194,共7页
Two-dimensional (2D) ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes were fabricated using an electrospinning-hydrothermal treatment-reduction method.Bare TiO2 nanotubes were fabricated via electrospinning.Then,2D ... Two-dimensional (2D) ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes were fabricated using an electrospinning-hydrothermal treatment-reduction method.Bare TiO2 nanotubes were fabricated via electrospinning.Then,2D MoS2 lamellae were grown on the surface of the nanotubes and Ti^3+/Ov ions were introduced by reduction.The photocatalytic performance of the 2D MoS2/Ti^3+-TiO2 nanotubes was^15 times better than that of TiO2.The HER enhancement of the MoS2/Ti^3+-TiO2 nanotubes can be attributed to the Pt-like behavior of 2D MoS2 and the presence of Ti^3+-ions,which facilitated the quick diffusion of the photogenerated electrons to water,reducing the H2 activation barrier.The presence of Ov ions in the nanotubes and their hollow structure increased their solar utilization. 展开更多
关键词 2d MOS2 TiO2 NANOTUBES Ti^3+self-doping Photocatalytic hydrogen production
下载PDF
A soluble FcγR homolog inhibits Ig M antibody production in ayu spleen cells 被引量:3
13
作者 Kai Chen Yu-Hong Shi +1 位作者 Jiong Chen Ming-Yun Li 《Zoological Research》 SCIE CAS CSCD 2019年第5期404-415,共12页
Classical Fc receptors (FcRs) mediate the binding to and recognition of the Fc portion of antibodies and play an important role during immune responses in mammals. Although proteins similar to soluble FcRs have been i... Classical Fc receptors (FcRs) mediate the binding to and recognition of the Fc portion of antibodies and play an important role during immune responses in mammals. Although proteins similar to soluble FcRs have been identified in fish, little is known about the role of such proteins in fish immunity. Here, we cloned a cDNA sequence encoding a soluble Fc receptor for an immunoglobulin G (FcγR) homolog from ayu (Plecoglossus altivelis)(PaFcγRl). The predicted protein was composed of two immunoglobulin C2-like domains but lacked a transmembrane segment and a cytoplasmic tail. The PaFcγRl transcripts were distributed at low levels in all tested tissues, but significantly increased after Vibrio anguillarum infection. The PaFcγRl protein was expressed in the head kidney, trunk kidney, and neutrophils. Recombinant PaFcγRl (rPaFcγRl) was secreted when transfected into mammalian cells and the native protein was also detected in serum upon infection. rPaFcγRl was also demonstrated to bind to ayu IgM, as assessed by cell transfection. Suppressive activity of the recombinant mature protein of PaFcγRl (rPaFcγRlm) on in vitro anti-sheep red blood cell (SRBC) responses was detected by a modified hemolytic plaque forming cell assay. In conclusion, our study revealed that PaFcγRl is closely involved in the negative regulation of IgM production in the ayu spleen. 展开更多
关键词 SOLUBLE FCΓr HOMOLOG Sequence characterization IgM-binding protein Inhibition of IGM production Plecoglossus altivelis
下载PDF
Perforation optimization of layer-penetration fracturing for commingling gas production in coal measure strata 被引量:5
14
作者 Bing Hou Zhuang Cui +3 位作者 Ji-Hui Ding Feng-Shou Zhang Li Zhuang Derek Elsworth 《Petroleum Science》 SCIE CAS CSCD 2022年第4期1718-1734,共17页
Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the eff... Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the effects of perforation position and length on hydraulic fracture propagation in coal measures of the Lin-Xing block,China.Based on field data,three lithologic combinations are simulated:1)a thick section of coal seam sandwiched by sandstones;2)a thin coal seam layer overlay by gas-bearing tight sandstone;3)two coal seams separated by a thin layer of sandstone.Our simulation shows that perforation position and length in multi-layer reservoirs play a major role in hydraulic fracture propagation.Achieving maximum stimulated volume requires consideration of lithologic sequence,coal seam thickness,stress states,and rock properties.To improve the combined gas production in coal measure strata,it is possible to simultaneously stimulate multiple coal seams or adjacent gas-bearing sandstones.In these cases,perforation location and length also significantly impact fracture propagation,and therefore should be carefully designed.Our simulation results using 3 D lattice algorithm are qualitatively consistent with laboratory physical simulation.3 D lattice models can be used to effectively simulate the fracture propagation through layers in coal measure strata.The numerical results provide guidance for perforation optimization in the hydraulic fracturing of coal measure strata. 展开更多
关键词 Coal measure strata Combined production 3d lattice algorithm Perforation scheme optimization Fracture propagation
下载PDF
MOF-Like 3D Graphene-Based Catalytic Membrane Fabricated by One-Step Laser Scribing for Robust Water Purification and Green Energy Production 被引量:3
15
作者 Xinyu Huang Liheng Li +11 位作者 Shuaifei Zhao Lei Tong Zheng Li Zhuiri Peng Runfeng Lin Li Zhou Chang Peng Kan-Hao Xue Lijuan Chen Gary J.Cheng Zhu Xiong Lei Ye 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第11期48-61,共14页
Increasing both clean water and green energy demands for survival and development are the grand challenges of our age.Here,we successfully fabricate a novel multifunctional 3D graphene-based catalytic membrane(3D-GCM)... Increasing both clean water and green energy demands for survival and development are the grand challenges of our age.Here,we successfully fabricate a novel multifunctional 3D graphene-based catalytic membrane(3D-GCM)with active metal nanoparticles(AMNs)loading for simultaneously obtaining the water purification and clean energy generation,via a“green”one-step laser scribing technology.The as-prepared 3D-GCM shows high porosity and uniform distribution with AMNs,which exhibits high permeated fluxes(over 100 L m^(−2) h^(−1))and versatile super-adsorption capacities for the removal of tricky organic pollutants from wastewater under ultra-low pressure-driving(0.1 bar).After adsorption saturating,the AMNs in 3D-GCM actuates the advanced oxidization process to self-clean the fouled membrane via the catalysis,and restores the adsorption capacity well for the next time membrane separation.Most importantly,the 3D-GCM with the welding of laser scribing overcomes the lateral shear force damaging during the long-term separation.Moreover,the 3D-GCM could emit plentiful of hot electrons from AMNs under light irradiation,realizing the membrane catalytic hydrolysis reactions for hydrogen energy generation.This“green”precision manufacturing with laser scribing technology provides a feasible technology to fabricate high-efficient and robust 3D-GCM microreactor in the tricky wastewater purification and sustainable clean energy production as well. 展开更多
关键词 3d graphene Laser scribing Catalytic membrane Water purification Hydrogen production
下载PDF
3D flower-like heterostructured TiO_2@Ni(OH)_2 microspheres for solar photocatalytic hydrogen production 被引量:5
16
作者 Wei Zhang Hongwen Zhang +2 位作者 Jianzhong Xu Huaqiang Zhuang Jinlin Long 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期320-325,共6页
TiO2@Ni(OH)2 core-shell microspheres were synthesized by a facile strategy to obtain a perfect 3D flower-like nanostructure with well-arranged Ni(OH)2 nanoflakes on the surfaces of TiO2 microspheres;this arrangement l... TiO2@Ni(OH)2 core-shell microspheres were synthesized by a facile strategy to obtain a perfect 3D flower-like nanostructure with well-arranged Ni(OH)2 nanoflakes on the surfaces of TiO2 microspheres;this arrangement led to a six-fold enhancement in photocatalytic hydrogen evolution. The unique p-n type heterostructure not only promotes the separation and transfer of photogenerated charge carriers significantly, but also offers more active sites for photocatalytic hydrogen production. A photocatalytic mechanism is proposed based on the results of electrochemical measurements and X-ray photoelectron spectroscopy. 展开更多
关键词 3d flower-like core-shell microspheres TiO2 NI(OH)2 Photocatalytic hydrogen production
下载PDF
L-LACTIC ACID FERMENTATION IN A ROTATING-DISC CONTACTOR WITH SIMULTANEOUS PRODUCT SEPARATION BY ION-EXCHANGE 被引量:2
17
作者 林建平 陈波 +1 位作者 吴坚平 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第1期53-59,共7页
A rotating disk contactor(RDC)was designed to perform L-lactic acid fermentation with afilamentous fungi,Rhizopus oryzae,which was immobilized on the surfaces of the rotating discs.Thebioreactor was operated using r... A rotating disk contactor(RDC)was designed to perform L-lactic acid fermentation with afilamentous fungi,Rhizopus oryzae,which was immobilized on the surfaces of the rotating discs.Thebioreactor was operated using repeated-batch method as well as continuous feeding method.Ananionic resin,D354,slightly basic in nature and of high selectivity and capacity was chosen for lacticacid separation.A coupled process of L-lactic acid fermentation and ion-exchange separation wasevaluated experimentally.The results indicated that the pH value of the fermentation broth could bemaintained at about 3-3.5 without any addition of alkali.The conversion ratio of glucose to L-lacticacid was about 0.7 g·g<sup>-1</sup> and the fermentation rate reached as high as 62.5 g·h<sup>-1</sup>·m<sup>-2</sup>. 展开更多
关键词 L-Lactic acid rOTATING-dISK CONTACTOr d354 resin coupled FErMENTATION and SEPArATION r. OrYZAE
下载PDF
Identification of single nucleotide polymorphisms of PIK3R1 and DUSP1 genes and their genetic associations with milk production traits in dairy cows 被引量:1
18
作者 Bo Han Yuwei Yuan +3 位作者 Lijun Shi Yanhua Li Lin Liu Dongxiao Sun 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第1期9-19,共11页
Background:Previously,phosphoinositide-3-kinase regulatory subunit 1(PIK3R1)and dual specificity phosphatase 1(DUSP1)were identified as promising candidate genes for milk production traits due to their being different... Background:Previously,phosphoinositide-3-kinase regulatory subunit 1(PIK3R1)and dual specificity phosphatase 1(DUSP1)were identified as promising candidate genes for milk production traits due to their being differentially expressed between the dry period and the peak of lactation in livers of dairy cows.Hence,in this study,the single nucleotide polymorphisms(SNPs)of PIK3R1 and DUSP1 genes were identified and their genetic associations with milk yield,fat yield,fat percentage,protein yield,and protein percentage,were investigated using 1067 Chinese Holstein cows from 40 sire families.Results:By re-sequencing the entire coding region and 2000 bp of the 5′and 3′flanking regions of the two genes,one SNP in the 5′untranslated region(UTR),three in the 3′UTR,and two in the 3′flanking region of PIK3R1 were identified,and one in the 5′flanking region,one in the 3′UTR,and two in the 3′flanking region of DUSP1 were found.Subsequent single-locus association analyses showed that five SNPs in PIK3 R1,rs42590258,rs210389799,rs208819656,rs41255622,rs133655926,and rs211408208,and four SNPs in DUSP1,rs207593520,rs208460068,rs209154772,and rs210000760,were significantly associated with milk,fat and protein yields in the first or second lactation(P values≤0.0001 and 0.0461).In addition,by the Haploview 4.2 software,the six and four SNPs in PIK3R1 and DUSP1 respectively formed one haplotype block,and the haplotype-based association analyses showed significant associations between their haplotype combinations and the milk traits in both two lactations(P values≤0.0001 and 0.0364).One SNP,rs207593520(T/G),was predicted to alter the transcription factor binding sites(TFBSs)in the 5′flanking region of DUSP1.Further,the dual-luciferase assay showed that the transcription activity of allele T in rs207593520 was significantly higher than that of allele G,suggesting the activation of transcriptional activity of DUSP1 gene by allele T of rs207593520.Thus,the rs207593520 SNP was highlighted as a potential causal mutation that should be further verified.Conclusions:We demonstrated novel and significant genetic effects of the PIK3R1 and DUSP1 genes on milk production traits in dairy cows,and our findings provide information for use in dairy cattle breeding. 展开更多
关键词 Chinese HOLSTEIN dUSP1 Genetic association MILK production PIK3r1 SNP
下载PDF
Spontaneous Resolution of Traumatic AV Malformation of the Uterus Following Hysteroscopic Cold Knife Evacuation of Retained Products of Conception 被引量:1
19
作者 Divyesh V. Shukla Shilpi D. Shukla +2 位作者 Amit Shah Sangita Patel Vaidehi Nene 《Open Journal of Obstetrics and Gynecology》 2020年第6期790-801,共12页
Uterine myometrial arteriovenous malformations (AVM) are reported on color doppler ultrasonography as mosaic pattern of blood flow with different peak systolic velocities (PSV) at different places. High PSV within the... Uterine myometrial arteriovenous malformations (AVM) are reported on color doppler ultrasonography as mosaic pattern of blood flow with different peak systolic velocities (PSV) at different places. High PSV within the AVM may require arterial embolization as treatment. However, we present a case of traumatic AVM with incomplete abortion managed by hysteroscopic cold knife evacuation. This case report is of a young patient with off and on vaginal bleeding for <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">3 1/2</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> months following 2</span><sup><span style="font-family:Verdana;">nd</span></sup><span style="font-family:Verdana;"> trimester spontaneous abortion. She had undergone dilation and evacuation (D & E) for incomplete abortion. Now the bleeding was heavy and intermittent not responding to medications. The subsequent TVS examination show</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> incomplete abortion with myometrial AVM with high PSV. Hysteroscopic cold knife removal of products of conception resulted in immediate resolution of Uterine AVM.</span></span></span> 展开更多
关键词 AVM Color doppler Cold Knife Evacuation d & E HYSTErOSCOPY retained products UTErUS PSV
下载PDF
Shale oil development techniques and application based on ternary-element storage and flow concept in Jiyang Depression,Bohai Bay Basin,East China
20
作者 YANG Yong 《Petroleum Exploration and Development》 SCIE 2024年第2期380-393,共14页
The ternary-element storage and flow concept for shale oil reservoirs in Jiyang Depression of Bohai Bay Basin,East China,was proposed based on the data of more than 10000 m cores and the production of more than 60 hor... The ternary-element storage and flow concept for shale oil reservoirs in Jiyang Depression of Bohai Bay Basin,East China,was proposed based on the data of more than 10000 m cores and the production of more than 60 horizontal wells.The synergy of three elements(storage,fracture and pressure)contributes to the enrichment and high production of shale oil in Jiyang Depression.The storage element controls the enrichment of shale oil;specifically,the presence of inorganic pores and fractures,as well as laminae of lime-mud rocks,in the saline lake basin,is conducive to the storage of shale oil,and the high hydrocarbon generating capacity and free hydrocarbon content are the material basis for high production.The fracture element controls the shale oil flow;specifically,natural fractures act as flow channels for shale oil to migrate and accumulate,and induced fractures communicate natural fractures to form complex fracture network,which is fundamental to high production.The pressure element controls the high and stable production of shale oil;specifically,the high formation pressure provides the drive force for the migration and accumulation of hydrocarbons,and fracturing stimulation significantly increases the elastic energy of rock and fluid,improves the imbibition replacement of oil in the pores/fractures,and reduces the stress sensitivity,guaranteeing the stable production of shale oil for a long time.Based on the ternary-element storage and flow concept,a 3D development technology was formed,with the core techniques of 3D well pattern optimization,3D balanced fracturing,and full-cycle optimization of adjustment and control.This technology effectively guides the production and provides a support to the large-scale beneficial development of shale oil in Jiyang Depression. 展开更多
关键词 Jiyang depression continental shale oil reservoir space fracturing stimulation fracture network storage and flow theory 3d development high and stable production
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部