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Nanoheterostructured photocatalysts for improving photocatalytic hydrogen production 被引量:24
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作者 hong du Ya‐Nan Liu +1 位作者 Cong‐Cong Shen An‐Wu Xu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第8期1295-1306,共12页
Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driv... Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driven by sunlight,is able to directly convert solar energy into a usable or storable energy resource,which is considered to be an ideal alternative energy source to assist in solving the energy crisis and environmental pollution.Unfortunately,the hydrogen production efficiency of single phase photocatalysts is too low to meet the practical requirements.The construction of heterostructured photocatalyst systems,which are comprised of multiple components or multiple phases,is an efficient method to facilitate the separation of electron‐hole pairs to minimize the energy‐waste,provide more electrons,enhance their redox ability,and hence improve the photocatalytic activity.We summarize the recent progress in the rational design and fabrication of nanoheterostructured photocatalysts.The heterojunction photocatalytic hydrogen generation systems can be divided into type‐I,type‐II,pn‐junction and Z‐scheme junction,according to the differences in the transfer of the photogenerated electrons and holes.Finally,a summary and some of the challenges and prospects for the future development of heterojunction photocatalytic systems are discussed. 展开更多
关键词 HETEROJUNCTION Conduction band Valence band Charge transfer Photocatalytic hydrogen production
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Intestinal stem cell marker LGR5 expression during gastric carcinogenesis 被引量:7
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作者 Zhi-Xue Zheng Yu Sun +9 位作者 Zhao-De Bu Lian-Hai Zhang Zi-Yu Li Ai-Wen Wu Xiao-Jiang Wu Xiao-hong Wang Xiao-Jing Cheng Xiao-Fang Xing hong du Jia-Fu Ji 《World Journal of Gastroenterology》 SCIE CAS 2013年第46期8714-8721,共8页
AIM:To investigate the differential expression of leu-cine-rich repeat-containing G protein-coupled receptor5(LGR5)in gastric cancer tissues and its significance related to tumor growth and spread.METHODS:Formalin-fix... AIM:To investigate the differential expression of leu-cine-rich repeat-containing G protein-coupled receptor5(LGR5)in gastric cancer tissues and its significance related to tumor growth and spread.METHODS:Formalin-fixed biopsy specimens of intestinal metaplasia(n=90),dysplasia(n=53),gastric adenocarcinoma(n=180),metastases in lymph nodes and the liver(n=15),and lesion-adjacent normal gastric mucosa(controls;n=145)were obtained for analysis from the Peking University Cancer Hospital’s Department of Pathology and Gastrointestinal Surgery tissue archives(January 2003 to December 2011).The biopsied patients’demographic and clinicopathologic data were retrieved from the hospital’s medical records database.Each specimen was subjected to histopathological typing to classify the tumor node metastasis(TNM)stage and to immunohistochemistry staining to detect the expression of the cancer stem cell marker LGR5.The intergroup differences in LGR5 expression were assessed by Spearman’s rank correlation analysis,and the relationship between LGR5 expression level and the patients’clinicopathological characteristics was evaluated by theχ2test or Fisher’s exact test.RESULTS:Significantly more gastric cancer tissues showed LGR5+staining than normal control tissues(all P<0.01),with immunoreactivity detected in 72.2%(65/90)and 50.9%(27/53)of intestinal metaplasia and dysplasia specimens,respectively,52.8%(95/180)of gastric adenocarcinoma specimens,and 73.3%%(11/15)of metastasis specimens,but 26.9%(39/145)of lesion-adjacent normal gastric mucosa specimens.Comparison of the intensity of LGR5+staining showed an increasing trend that generally followed increasing dedifferentiation and tumor spread(normal tissue<dysplasia,<gastric adenocarcinoma<metastasis;all P<0.001),with the exception of expression level detected in intestinal metaplasia which was higher than that in normal gastric tissues(P<0.001).Moreover,gastric cancer-associated enhanced expression of LGR5 was found to be signifcantly associated with age,tumor differentiation,Lauren type and TNM stage(Ⅰ+ⅡvsⅢ+Ⅳ)(all P<0.05),but not with sex,tumor site,location,size,histology,lymphovascular invasion,depth of invasion,lymph node metastasis or distant metastasis.Patients with LGR5+gastric cancer specimens and without signs of metastasis from the original biopsy experienced more frequent rates of recurrence or metastasis during follow-up than patients with LGR5-specimens(P<0.05).CONCLUSION:Enhanced LGR5 is related to progressive dedifferentiation and metastasis of gastric cancer,indicating the potential of this receptor as an early diagnostic and prognostic biomarker. 展开更多
关键词 Leucine-rich repeat-containing G protein-coupled receptor 5 CANCER stem cell Gastric CANCER INTESTINAL METAPLASIA Tumorigenesis
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Predictive factors of endoscopic submucosal dissection procedure time for gastric superficial neoplasia 被引量:6
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作者 Zhong-Sheng Lu Yun-Sheng Yang +7 位作者 Dan Feng Shu-Fang Wang Jing Yuan Jin Huang Xiang-Dong Wang Jiang-Yun Meng hong du hong-Bin Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第47期7009-7014,共6页
AIM:To identify the determinants of endoscopic submucosal dissection(ESD) operation time.METHODS:This investigation was conducted as a single-center,prospective study in which ESD was performed by the same endoscopist... AIM:To identify the determinants of endoscopic submucosal dissection(ESD) operation time.METHODS:This investigation was conducted as a single-center,prospective study in which ESD was performed by the same endoscopist at the Chinese PLA General Hospital.A total of 173 patients underwent ESD operations performed by Dr.Lu from July 2007 to December 2011,and 183 lesions were enrolled.Patient gender,age,tumor location,gross type,tumor size,pathological type and adhesions were recorded prospectively.The order of treatment represented the experience of the operator.Univariate analysis and multivariate analysis were performed to evaluate the relationships between these factors and ESD procedure time.RESULTS:Univariate analysis showed the ESD time was closely related to the gender(P = 0.0210),tumor size(P < 0.0001),location(P < 0.0001),gross type(P < 0.0001) and adhesion(P = 0.0010).The surgical proficiency level was associated with ESD time in unit area(P < 0.0001).Multivariate analysis revealed that the ESD time was positively correlated with tumor size(P < 0.0001),adhesion(P < 0.0001) and location(P < 0.0001),but negatively correlated with surgical proficiency level(P = 0.0046).CONCLUSION:Large tumor size,adjacency to the cardia,and adhesion are predictors of a long ESD time,whereas high surgical proficiency level predicts a short ESD time. 展开更多
关键词 Endoscopic submucosal dissection Procedure time Gastric superficial neoplasia Predictive factors
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Novel endoscopic papillectomy for reducing postoperative adverse events(with videos) 被引量:4
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作者 Lei Jiang En-Qiang Ling-Hu +10 位作者 Ning-Li Chai Wen Li Feng-Chun Cai Ming-Yang Li Xu Guo Jiang-Yun Meng Xiang-Dong Wang Ping Tang Jing Zhu hong du hong-Bin Wang 《World Journal of Gastroenterology》 SCIE CAS 2020年第40期6250-6259,共10页
BACKGROUND Pancreatic adenoma can potentially transform into adenocarcinoma, so it is recommended to be resected surgically or endoscopically. Endoscopic papillectomy is one of the main treatments for papillary adenom... BACKGROUND Pancreatic adenoma can potentially transform into adenocarcinoma, so it is recommended to be resected surgically or endoscopically. Endoscopic papillectomy is one of the main treatments for papillary adenoma, and bleeding, perforation, and pancreatitis are the most frequent and critical adverse events that restrict its wider use. There is no standard procedure for endoscopic papillectomy yet. The procedure is relevant to postoperative adverse events.AIM To reduce the postoperative adverse event rates and improve patients' postoperative condition, we developed a standard novel procedure for endoscopic papillectomy.METHODS The novel endoscopic papillectomy had two main modifications based on the conventional method: The isolation of bile from pancreatic juice with a bile duct stent and wound surface protection with metal clips and fibrin glue. We performed a single-center retrospective comparison study on the novel and conventional methods to examine the feasibility of the novel method for reducing postoperative adverse events.RESULTS A total of 76 patients, of whom 23 underwent the novel procedure and 53 underwent the conventional procedure, were retrospectively evaluated in this study. The postoperative bleeding and pancreatitis rates of the novel method were significantly lower than those of the conventional method(0 vs 20.75%, P = 0.028, and 17.4% vs 41.5%, P = 0.042, respectively). After applying the novel method, the most critical adverse event, perforation, was entirely prevented, compared to a prevalence of 5.66% with the conventional method. Several postoperative symptoms, including fever, rapid pulse, and decrease in hemoglobin level, were significantly less frequent in the novel group(P = 0.042, 0.049, and 0.014, respectively). Overall, the total adverse event rate of the novel method was lower(0 vs 24.5%, P = 0.007) than that of the conventional method.CONCLUSION Patients who underwent the novel procedure had lower postoperative adverse event rates. This study demonstrates the potential efficacy and safety of the novel endoscopic papillectomy in reducing postoperative adverse events. 展开更多
关键词 Endoscopic papillectomy Novel technique Adverse events Papillary adenoma Endoscopic retrograde cholangiopancreatography Bile duct stent
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Different methods of acupuncture for relief of pain due to liver cancer:A network meta-analysis 被引量:1
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作者 hong-Yuan Mou Jing Chen +1 位作者 Zuo-Yun Chen hong du 《World Journal of Meta-Analysis》 2022年第2期52-62,共11页
BACKGROUND Pain in the liver is a common symptom of liver cancer in late stages,and the pain incidence rate exceeds 50%[1].In serious cancer pain,morphine and other major analgesics have been commonly administrated fo... BACKGROUND Pain in the liver is a common symptom of liver cancer in late stages,and the pain incidence rate exceeds 50%[1].In serious cancer pain,morphine and other major analgesics have been commonly administrated for clinical treatments,and their effects are accurate,but with a high incidence of side effects,such as nausea,vomiting,constipation,and other conditions.Acupuncture is a traditional Chinese medicine therapy.There have been many randomized controlled trials addressing the safety and usefulness of different methods of acupuncture in alleviating liver cancer pain.However,which of these methods is the most effective method is still unclear.AIM To compare the effectiveness of different acupuncture methods for alleviating pain due to liver cancer.METHODS Eligible studies were retrieved from eight databases(the Cochrane Library,PubMed,EMBASE,Medline,CNKI,CBM,Chongqing VIP,and Wan Fang Database)up to March 31,2021 and screened based on the established inclusion and exclusion criteria.The quality of the include studies was evaluated.Stata software was applied for statistical analyses.Publication bias of the included studies was also determined.Finally,the network meta-analysis was carried out to evaluate the efficacy of acupuncture methods for relief of pain due to liver cancer.RESULTS A total of eight randomized controlled trials were included in the network metaanalysis.Eight trials(covering 5 treatments and 734 patients)provided data suitable for analysis.Most trials focused on short-term effects and many were classed as being of poor quality with a high risk of bias,commonly associated with lack of blinding(which was sometimes impossible to achieve).End of treatment results showed that four interventions,including wrist-ankle acupuncture,triple puncture and remaining needle acupuncture,Tian Yuan acupuncture,and block acupuncture,produced a statistically significant reduction in pain when compared with the three-step analgesic ladder therapy.The surface under the cumulative ranking sorting results showed that triple puncture and remaining needle acupuncture had a relatively high effective rate.CONCLUSION The network meta-analysis results indicate that the overall effectiveness of triple puncture and remaining needle acupuncture is better than the other therapies. 展开更多
关键词 PAIN Liver cancer ACUPUNCTURE Network meta-analysis EFFECTIVENESS Three-step analgesic ladder
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慕课西行背景下新疆师范大学化学专业核心课程多校多向同步课堂智慧教学探索实践
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作者 关明 白希 +11 位作者 马玉花 米芳 范维刚 郭俊杰 李桂新 王英波 曾涵 曾竟 肖璐 李茵萍 杜虹 高雅 《大学化学》 2025年第11期59-65,共7页
教育部明确提出实施“慕课西部行计划”,强调数智赋能,更好地实现因材施教。新疆师范大学化学专业核心课程教学团队,以新时代党的治疆方略为指引,以培养西部区域性人才为导向,依托“智慧树”平台,借助东西部高校课程共享联盟优质资源,... 教育部明确提出实施“慕课西部行计划”,强调数智赋能,更好地实现因材施教。新疆师范大学化学专业核心课程教学团队,以新时代党的治疆方略为指引,以培养西部区域性人才为导向,依托“智慧树”平台,借助东西部高校课程共享联盟优质资源,运用知识图谱与AI共享课程,作为合作方与疆外名校合作,又作为开课方与疆内高校合作,开展同步课堂,共建知识图谱,实现多校教学资源共享、多向同步课堂共享、数智赋能平台共享,构建了多校多向同步课堂新型合作模式与基于人工智能知识图谱的新型教学形态。 展开更多
关键词 数智赋能 慕课西行 化学专业核心课程 同步课堂 教学新形态
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Yb_(2)O_(3)改性硅黏结层的环境障涂层体系耐高温水氧腐蚀行为研究
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作者 梁锐辉 钟鑫 +3 位作者 洪督 黄利平 牛亚然 郑学斌 《无机材料学报》 北大核心 2025年第4期425-432,共8页
稀土硅酸盐环境障涂层(EBCs)是应用于新一代高推重比航空发动机热端部件的重要材料。但在服役过程中,硅黏结层的氧化和开裂是导致EBCs失效的重要因素。对硅黏结层进行改性成为延长EBCs服役寿命的重要手段。本研究在硅黏结层中掺杂Yb_(2)... 稀土硅酸盐环境障涂层(EBCs)是应用于新一代高推重比航空发动机热端部件的重要材料。但在服役过程中,硅黏结层的氧化和开裂是导致EBCs失效的重要因素。对硅黏结层进行改性成为延长EBCs服役寿命的重要手段。本研究在硅黏结层中掺杂Yb_(2)O_(3)来缓解高温水氧环境下涂层开裂的问题,并提高其耐高温水氧腐蚀性能。通过真空等离子喷涂技术在SiC基体上制备了五种不同Yb_(2)O_(3)掺杂量(0、5%、10%、15%、20%,体积分数)的EBCs体系(Si-Yb_(2)O_(3))/Yb_(2)Si_(2)O_(7)/Yb_(2)SiO_(5),并研究其在1350℃下的耐水氧腐蚀行为和机理。结果表明,掺杂适量(5%)的Yb_(2)O_(3)能够在高温水氧腐蚀过程中反应并消耗SiO_(2),减少SiO_(2)相变(β→α)带来的应力变化,抑制混合热生长氧化(mTGO)层纵向裂纹的产生,达到提高结构稳定性的效果。另外,反应生成的Yb_(2)Si_(2)O_(7)具有合适的热膨胀系数(CTE)和化学相容性。然而,随着Yb_(2)O_(3)掺杂量提高,过量的Yb_(2)O_(3)会在黏结层内部相互联结并形成“骨架”结构,为氧化性物质提供向涂层内部扩散的直接通道,使黏结层内部发生腐蚀,导致涂层体系耐水氧腐蚀性能下降。 展开更多
关键词 环境障涂层 水氧腐蚀 黏结层改性 真空等离子喷涂
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TiAl合金表面等离子喷涂制备新型热障涂层沉积过程的热应力演化有限元模拟
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作者 谢玲玲 方天宇 +4 位作者 牛亚然 洪督 王子昱 祝世超 郑学斌 《表面技术》 北大核心 2025年第11期231-242,共12页
目的揭示TiAl合金表面等离子喷涂热障涂层沉积过程热应力的分布和演化规律,降低因残余应力过大导致涂层开裂失效的可能性,为制备新型TiAlCrY/YSZ TBCs应力状态精确可控涂层提供指导。方法基于有限元模拟,针对TiAl合金表面等离子喷涂TiAl... 目的揭示TiAl合金表面等离子喷涂热障涂层沉积过程热应力的分布和演化规律,降低因残余应力过大导致涂层开裂失效的可能性,为制备新型TiAlCrY/YSZ TBCs应力状态精确可控涂层提供指导。方法基于有限元模拟,针对TiAl合金表面等离子喷涂TiAlCrY/YSZ新型热障涂层的沉积过程,采用逐道逐层喷涂的方式进行三维热力耦合模拟,获得较好的热应力分布和演变规律。结果在TiAlCrY过渡层和YSZ涂层的喷涂过程中,对于x、y方向的应力,熔道的大部分区域均为压应力,但在熔道起始位置存在较小的拉应力,在熔道末尾位置存在很大的压应力;对于z向应力,熔道表面为拉-压应力交替,在熔道末尾存在较高的拉应力。由于材料的属性存在明显差异,因此各层材料的界面处存在应力突变现象。在喷涂过程中,由于层与层、道与道之间存在相互的热影响,因此沉积过程中存在多次热应力循环过程,尤其是沉积过程中出现的拉应力和压应力峰值均明显高于冷却至室温后的残余应力。结论不同材料的界面处是应力发生突变的区域,且在沉积过程中多道、多次热应力循环会产生拉应力和压应力峰值,这更易导致涂层发生开裂。 展开更多
关键词 三维热力耦合模拟 等离子喷涂 逐道逐层 热障涂层 热应力
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(Hf_(1/4)Zr_(1/4)Ta_(1/4)Ti_(1/4))B_(2)-SiC复相高熵陶瓷高温氧化行为与机理研究
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作者 徐以祥 洪督 +4 位作者 黄山松 黄利平 刘吉轩 牛亚然 郑学斌 《材料保护》 2025年第10期34-43,共10页
高熵硼化物的氧化行为和SiC第二相的影响机制对其在极端环境下的应用至关重要,然而目前相关研究还比较有限。本工作采用放电等离子烧结技术制备了SiC含量(体积分数)分别为10%和20%的(Hf_(1/4)Zr_(1/4)Ta_(1/4)Ti_(1/4))B_(2)-SiC复相陶... 高熵硼化物的氧化行为和SiC第二相的影响机制对其在极端环境下的应用至关重要,然而目前相关研究还比较有限。本工作采用放电等离子烧结技术制备了SiC含量(体积分数)分别为10%和20%的(Hf_(1/4)Zr_(1/4)Ta_(1/4)Ti_(1/4))B_(2)-SiC复相陶瓷,采用高温管式炉进行了氧化测试,表征了其在1 500℃下的氧化行为,包括氧化增重、氧化产物相组成与结构特征等,并与单相(Hf_(1/4)Zr_(1/4)Ta_(1/4)Ti_(1/4))B_(2)进行比较。结果发现,SiC第二相能显著降低(Hf_(1/4)Zr_(1/4)Ta_(1/4)Ti_(1/4))B_(2)的氧化失重现象,减少氧化层的厚度与内部缺陷,增加氧化层的阻氧能力。结合热力学计算分析了可能的氧化过程和SiC添加相的作用机制,以期为高熵硼化物的高温应用提供参考。 展开更多
关键词 高熵陶瓷 超高温陶瓷 硼化物 氧化行为
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清肺化纤方通过抑制PI3K/Akt阻断EMT抗肺纤维化作用
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作者 洪都 肖颖 +2 位作者 宋康 张卓一 郑兰芝 《浙江临床医学》 2025年第12期1747-1750,共4页
目的探讨清肺化纤方治疗特发性肺纤维化(IPF)的潜在作用机制。方法采用网络药理学方法筛选清肺化纤方治疗IPF的关键靶点及核心信号通路,并通过体外细胞实验进行验证。将A549细胞分为TGF-β1组、对照组、TGF-β1+溶剂组以及含药血清组。... 目的探讨清肺化纤方治疗特发性肺纤维化(IPF)的潜在作用机制。方法采用网络药理学方法筛选清肺化纤方治疗IPF的关键靶点及核心信号通路,并通过体外细胞实验进行验证。将A549细胞分为TGF-β1组、对照组、TGF-β1+溶剂组以及含药血清组。含药血清组使用10%清肺化纤方含药血清处理细胞48 h,采用Western blot、RT-qPCR及免疫荧光法检测清肺化纤方含药血清对PI3k/Akt信号通路及A549细胞上皮-间质转化(EMT)的影响。结果网络药理学分析共筛选出清肺化纤方与IPF的共同作用靶点261个;KEGG富集分析得到181条相关通路,主要包括AGE-RAGE、IL-17、TNF及PI3K-Akt等信号通路。细胞实验结果表明,清肺化纤方可下调PI3K/Akt信号通路相关蛋白表达,抑制EMT过程,从而发挥抗肺纤维化作用。结论清肺化纤方可能通过多成分、多靶点、多通路的方式治疗IPF,其机制与调控PI3K/Akt信号通路、抑制EMT过程有关,为该方的临床应用与开发提供了理论依据。 展开更多
关键词 清肺化纤方 网络药理学 肺纤维化 PI3K/AKT信号通路 上皮-间质转化
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农村偏远地区弱联系统微网供电模式配置方法 被引量:1
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作者 金家桢 孔令威 +2 位作者 洪度 谌思桐 杨韵祺 《电工材料》 2025年第2期109-112,共4页
灌溉、电动机、照明和其他电力用途都越来越依赖太阳能,将太阳能系统集成到农村微电网中变得越来越重要。基于此,提出了基于光伏的微电网的非线性DC/DC转换器的建模和管理,这种方法的主要优点是转换器模型可以线性化,从而扩大了可能的... 灌溉、电动机、照明和其他电力用途都越来越依赖太阳能,将太阳能系统集成到农村微电网中变得越来越重要。基于此,提出了基于光伏的微电网的非线性DC/DC转换器的建模和管理,这种方法的主要优点是转换器模型可以线性化,从而扩大了可能的工作点范围。单端初级电感变换器和升压变换器都用于将光伏模块的电力转换为更高的电压形式,并通过MATLAB的仿真结果证明了所建议的控制的效率。 展开更多
关键词 DC/AC DC/DC 微型逆变器 可再生电力 农村微电网
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Evapotranspiration and Its Components Partitioning Based on an Improved Hydrological Model:Historical Attributions and Future Projections
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作者 hong du Sidong Zeng +1 位作者 Yongyue Ji Jun Xia 《Journal of Earth Science》 2025年第6期2689-2707,共19页
Estimation and attribution of evapotranspiration(ET)and its components under changing environment is still a challenge but is essential for understanding the mechanisms of water and energy transfer for regional water ... Estimation and attribution of evapotranspiration(ET)and its components under changing environment is still a challenge but is essential for understanding the mechanisms of water and energy transfer for regional water resources management.In this study,an improved hydrological model is developed to estimate evapotranspiration and its components,i.e.,evaporation(E)and transpiration(T)by integrated the advantages of hydrological modeling constrained by water balance and the water-carbon close relationships.Results show that the improved hydrological model could captures ET and its components well in the study region.During the past years,annual ET and E increase obviously about 2.40 and 1.42 mm/a,particularly in spring and summer accounting for 90%.T shows less increasement and mainly increases in spring while it decreases in summer.Precipitation is the dominant factor and contributes 74.1%and 90.0%increases of annual ET and E,while the attribution of T changes is more complex by coupling of the positive effects of precipitation,rising temperature and interactive influences,the negative effects of solar diming and elevated CO_(2).In the future,ET and its components tend to increase under most of the Shared Socioeconomic Pathways(SSP)scenarios except for T decreases under the very high emissions scenario(SSP5-8.5)based on the projections.From seasonal perspective,the changes of ET and the components are mainly in spring and summer accounting for 75%,while more slight changes are found in autumn and winter.This study highlights the effectiveness of estimating ET and its components by improving hydrological models within water-carbon coupling relationships,and more complex mechanisms of transpiration changes than evapotranspiration and evaporation changes under the interactive effects of climate variability and vegetation dynamics.Besides,decision makers should pay attention to the more increases in the undesirable E than desirable T. 展开更多
关键词 EVAPOTRANSPIRATION ET components attribution analysis future projections water resources HYDROGEOLOGY
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固酶纳米复合物光电催化性能评估的综合实验——多学科交叉综合性实验教学改革实践 被引量:1
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作者 杜虹 张咪 曾涵 《大学化学》 CAS 2023年第5期234-240,共7页
针对现有固酶二氧化钛-碳纳米材料复合物基光电化学传感器存在的环境适应性和抗干扰性欠佳、灵敏度和底物选择性不够高以及构效关系研究不足等问题,系统探讨了不同功能单元与二氧化钛/碳基纳米材料之间各种相互作用与纳米复合物各基元... 针对现有固酶二氧化钛-碳纳米材料复合物基光电化学传感器存在的环境适应性和抗干扰性欠佳、灵敏度和底物选择性不够高以及构效关系研究不足等问题,系统探讨了不同功能单元与二氧化钛/碳基纳米材料之间各种相互作用与纳米复合物各基元结构、组成以及理化性质之间的关联。在此基础上确定制约其传感效能和应用价值的关键因素,阐述了未来构筑此类传感器构效关系模型所需解决的重点问题。本文设计了一个典型的综合性实验,介绍了固载牛血红蛋白的二氧化钛纳米球-3D氧化石墨烯共价偶联复合物基电极的制备方法。使学生掌握综合运用多种表征测试技术考察固载酶分子与载体各基元间相互作用对酶参与光电催化反应各相关步骤动力学的影响的方法,并了解固酶电极光电催化动力学参数测定的相关理论和方法。 展开更多
关键词 二氧化钛 碳纳米材料 光电化学传感器 综合性实验 催化动力学
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二硅化钼改性硅酸镱环境障涂层体系抗热震行为及机理 被引量:2
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作者 梁锐辉 钟鑫 +6 位作者 洪督 黄利平 吴一鸣 赵芳霞 牛亚然 张振忠 郑学斌 《航空材料学报》 CAS CSCD 北大核心 2023年第4期37-44,共8页
稀土硅酸盐环境障涂层(EBCs)是应用于新一代高推重比航空发动机热端部件的重要材料,但在服役过程中,稀土硅酸盐面层易产生纵向裂纹,为腐蚀性介质进入EBCs体系内部提供通道,使硅黏结层发生氧化并产生裂纹,最终导致EBCs失效。二硅化钼(MoS... 稀土硅酸盐环境障涂层(EBCs)是应用于新一代高推重比航空发动机热端部件的重要材料,但在服役过程中,稀土硅酸盐面层易产生纵向裂纹,为腐蚀性介质进入EBCs体系内部提供通道,使硅黏结层发生氧化并产生裂纹,最终导致EBCs失效。二硅化钼(MoSi_(2))具有优异的高温性能,有望改善稀土硅酸盐EBCs体系的高温稳定性。本工作采用MoSi_(2)改性Yb_(2)SiO_(5)面层,通过真空等离子喷涂技术(VPS)分别制备了以Yb2SiO5、Yb_(2)SiO_(5)-5%MoSi_(2)(体积分数,下同)和Yb_(2)SiO_(5)-10%MoSi_(2)作为面层,以Yb_(2)Si_(2)O_(7)作为中间层,以Si作为黏结层的三种环境障涂层体系,利用场发射扫描电子显微镜表征了涂层在1350℃热震前后的形貌变化。结果表明:掺杂MoSi_(2)不仅能改善涂层的损伤容限,还可消耗氧化性介质,减少其向涂层体系内部的扩散,使黏结层上TGO层厚度分别降低83%和88%,从而有效改善涂层体系的高温稳定性。 展开更多
关键词 环境障碍涂层 硅酸镱 MoSi_(2) 热震 真空等离子喷涂
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大型气液同轴喷射分布器数学模拟 被引量:2
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作者 洪都 高用祥 +2 位作者 成有为 王丽军 李希 《化学反应工程与工艺》 CAS 北大核心 2019年第1期1-8,17,共9页
大型浆态床的气液分布器设计需要同时考虑气体均布、气液传质和防止堵塞三个方面的要求,基于此提出了一种大孔径气液同轴喷射的分布器构型.首先通过单喷嘴冷模实验测量了全塔平均气含率和大、小气泡相含率,证明气液同轴喷射能够显著强... 大型浆态床的气液分布器设计需要同时考虑气体均布、气液传质和防止堵塞三个方面的要求,基于此提出了一种大孔径气液同轴喷射的分布器构型.首先通过单喷嘴冷模实验测量了全塔平均气含率和大、小气泡相含率,证明气液同轴喷射能够显著强化气液传质,减小气泡直径.随后对所设计的外径6.3 m的多环大型气液分布器内部的流动进行了三维瞬态模拟以探讨改进气体均布的措施,模拟发现,对于多环分布管结构,采用管径随环径增大的变直径分布器代替常用的等直径分布器能够明显改善气体分布的均匀性.最后对该分布器在不同载荷下的气体均布指标进行了计算机模拟,结果表明在±40%的负荷变化范围内,分布器的气体均布性能仍然比较稳定,能够满足工业应用的要求. 展开更多
关键词 鼓泡塔 气液分布器 气液同轴喷射 气液均布 计算流体力学
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喷射环流反应器的放大效应 被引量:1
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作者 高用祥 洪都 +2 位作者 成有为 王丽军 李希 《高校化学工程学报》 EI CAS CSCD 北大核心 2019年第3期579-586,共8页
实验测量了两种塔径( 200 和 500 mm)和两种操作模式(气体单独喷射和气液同轴喷射)下喷射环流反应器内的全塔平均气含率、局部气含率及轴向液速径向分布、循环液速,归纳出全塔平均气含率的关联式。实验发现,喷射环流反应器具有十分显著... 实验测量了两种塔径( 200 和 500 mm)和两种操作模式(气体单独喷射和气液同轴喷射)下喷射环流反应器内的全塔平均气含率、局部气含率及轴向液速径向分布、循环液速,归纳出全塔平均气含率的关联式。实验发现,喷射环流反应器具有十分显著的放大效应。小塔( 200)与大塔( 500)中的全塔平均气含率存在很大差异:小塔的全塔平均气含率~气速关系曲线比大塔陡峭,低气速下小塔气含率低于大塔、较高气速下高于大塔。根据漂移通量法分析得到小塔中流型转变点在表观气速 0.1 m s 1左右,在实验气速范围内只存在拟均匀鼓泡流;大塔中流型转变点在表观气速 0.04 m s 1左右,随气速增大从拟均匀鼓泡流转变为湍动鼓泡流。喷射环流反应器比气升式环流反应器、一般鼓泡塔全塔平均气含率略低,但循环液速更大,适用于强化固体悬浮与混合的气液固三相反应过程。 展开更多
关键词 鼓泡塔 喷射环流反应器 放大效应 气含率 循环液速
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等离子喷涂TiC-Graphite复合涂层摩擦磨损性能 被引量:1
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作者 洪督 牛亚然 +2 位作者 李红 钟鑫 郑学斌 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2022年第6期643-650,共8页
等离子喷涂TiC涂层具有良好的综合性能,在极端环境能起到较好的耐磨保护作用,而石墨是一种优异的自润滑材料。通过喷雾干燥与真空烧结技术制备不同石墨添加量(1.25%、2.5%、5%和10%,质量分数)的TiC-Graphite球形粉体,并采用大气等离子... 等离子喷涂TiC涂层具有良好的综合性能,在极端环境能起到较好的耐磨保护作用,而石墨是一种优异的自润滑材料。通过喷雾干燥与真空烧结技术制备不同石墨添加量(1.25%、2.5%、5%和10%,质量分数)的TiC-Graphite球形粉体,并采用大气等离子喷涂技术制备TiC-Graphite复合涂层。对涂层的相组成、显微结构和力学性能进行了表征,并对涂层的摩擦磨损性能进行了比较研究。结果发现,TiC-Graphite涂层主要由TiC和石墨相组成。随石墨添加量增大,TiC-Graphite涂层截面微裂纹增多,表面粗糙度增大,硬度下降。石墨对TiC涂层在高载荷的磨损性能影响更显著。在50 N高载荷条件,随石墨添加量增大,TiC-Graphite涂层磨损率降低后急剧增大,而摩擦系数持续减小。当石墨添加量为2.5%时,涂层获得最低的磨损率为0.67×10^(−5) mm^(3)/(N·m),同时具有较低的摩擦系数(0.35),与不添加石墨的TiC涂层相比,分别降低了72.4%和27.8%。 展开更多
关键词 TiC-Graphite复合涂层 磨损性能 大气等离子喷涂 显微结构 力学性能
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TiAl合金表面TiAlCrY/YSZ涂层高温长时间服役性能 被引量:1
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作者 潘洋洋 梁波 +3 位作者 洪督 祁志祥 牛亚然 郑学斌 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2023年第1期105-112,共8页
TiAl合金具有低密度、高比强度的优异性能,是一种潜在的航空发动机用结构材料。TiAl合金的服役温度范围为700~900℃,在其表面制备高温热防护涂层可以进一步提高服役温度。本研究采用等离子喷涂技术在TiAl合金表面制备了新型TiAlCrY/YSZ... TiAl合金具有低密度、高比强度的优异性能,是一种潜在的航空发动机用结构材料。TiAl合金的服役温度范围为700~900℃,在其表面制备高温热防护涂层可以进一步提高服役温度。本研究采用等离子喷涂技术在TiAl合金表面制备了新型TiAlCrY/YSZ涂层,并与传统的NiCrAlY/YSZ热障涂层进行高温长时间服役性能对比研究。结果发现,TiAlCrY/YSZ涂层在1100℃空气环境中服役300 h保持完好,表现出良好的高温性能,而NiCrAlY/YSZ涂层在1100℃的服役寿命不足100 h。显微分析结果表明,TiAlCrY黏结层表面会形成一层连续且致密的TGO,其主要成分为Al2O3,与YSZ涂层的界面兼容性良好。并且TGO在1100℃空气环境中服役300 h后,厚度仍<8μm。以上研究表明,与传统NiCrAlY/YSZ热障涂层相比,TiAlCrY/YSZ更适合作为TiAl合金表面的高温热防护涂层。 展开更多
关键词 TIAL合金 TiAlCrY/YSZ涂层 等离子喷涂 高温长时间服役性能
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Hantavirus infection:a global zoonotic challenge 被引量:59
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作者 hong Jiang Xuyang Zheng +3 位作者 Limei Wang hong du Pingzhong Wang Xuefan Bai 《Virologica Sinica》 SCIE CAS CSCD 2017年第1期32-43,共12页
Hantaviruses are comprised of tri-segmented negative sense single-stranded RNA, and are members of the Bunyaviridae family. Hantaviruses are distributed worldwide and are important zoonotic pathogens that can have sev... Hantaviruses are comprised of tri-segmented negative sense single-stranded RNA, and are members of the Bunyaviridae family. Hantaviruses are distributed worldwide and are important zoonotic pathogens that can have severe adverse effects in humans. They are naturally maintained in specific reservoir hosts without inducing symptomatic infection. In humans, however,hantaviruses often cause two acute febrile diseases, hemorrhagic fever with renal syndrome(HFRS) and hantavirus cardiopulmonary syndrome(HCPS). In this paper, we review the epidemiology and epizootiology of hantavirus infections worldwide. 展开更多
关键词 HANTAVIRUS Bunyaviridae zoonosis hemorrhagic fever with renal syndrome hantavirus cardiopulmonary syndrome
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