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冀北山地不同坡向白桦枝叶异速生长关系研究

西北林学院学报 2024年第1期39卷 52-58,66页

作者：许竹锐王世虎高青青于小萌徐学华河北农业大学林学院河北保定071000

当年生小枝作为植物生长的独立构件单元,研究其大小关系对于理解植物生存适应策略具有重要意义。以冀北山地不同坡向白桦枝叶为研究对象,测定小枝的茎干质量、叶片干质量、叶片面积、叶柄干质量以及小枝干质量,分析不同坡向白桦枝叶生... 详细信息

当年生小枝作为植物生长的独立构件单元,研究其大小关系对于理解植物生存适应策略具有重要意义。以冀北山地不同坡向白桦枝叶为研究对象,测定小枝的茎干质量、叶片干质量、叶片面积、叶柄干质量以及小枝干质量,分析不同坡向白桦枝叶生长关系,揭示白桦枝叶生长对坡向的生态策略和适应性。结果表明:(1)除茎干质量外,其余干质量皆显示为半阳坡显著大于阴坡,叶片面积在坡向间无显著差异。(2)标准化主轴回归分析(SMA)表明,在小枝水平上,不同坡向间茎干质量与小枝干质量、总叶片干质量与小枝干质量、总叶片面积与小枝干质量均为等速关系,而总叶柄干质量与小枝干质量为异速关系;且茎干质量与小枝干质量、总叶柄干质量与小枝干质量的共同斜率1.12和1.22大于总叶片干质量与小枝干质量的共同斜率1.04。(3)在叶水平上,阴坡和半阳坡总叶片干质量与总叶柄干质量为异速关系,在半阴坡为等速关系;总叶片面积与总叶柄干质量在阴坡为等速关系,其余坡向为异速关系。(4)每个坡向叶大小与出叶强度呈负等速关系;叶大小以叶干质量表示时,阴坡异速生长常数-0.18为最小;叶大小以叶面积表示时,半阳坡异速生长常数2.01为最小。结果表明,白桦为适应坡向的变化,会优先将资源分配给茎和叶柄,且阴坡白桦小枝上会着生更多面积大而干质量小的叶片,以扩展其生长空间,获得更多的光照,利于白桦的生长。

关键词：白桦枝叶性状生长策略异速生长

大容量套扎器套扎与组织胶联合聚桂醇注射治疗GOV型胃底静脉曲张的比较研究

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天津医药 2024年第6期52卷 604-609页

作者：石玉茹石定河南中医药大学第一附属医院消化科 450000 宁波市第二医院消化科

目的比较大容量套扎器与组织胶注射治疗食管胃静脉曲张(GOV)型胃静脉曲张的疗效和安全性,为GOV型胃静脉曲张的治疗提供参考。方法前瞻性纳入150例GOV型胃静脉曲张患者。结合患者病情及意愿将患者分为内镜下曲张静脉套扎术(EBL组,78例)... 详细信息

目的比较大容量套扎器与组织胶注射治疗食管胃静脉曲张(GOV)型胃静脉曲张的疗效和安全性,为GOV型胃静脉曲张的治疗提供参考。方法前瞻性纳入150例GOV型胃静脉曲张患者。结合患者病情及意愿将患者分为内镜下曲张静脉套扎术(EBL组,78例)和内镜下曲张静脉栓塞术(EVO组,72例)。EBL组采用大容量套扎器对GOV型胃静脉曲张进行内镜下套扎治疗;EVO组使用组织胶联合聚桂醇注射治疗。所有患者于首次术后2~3周复查胃镜,观察有无曲张静脉残留及出血(若有,此次随访时需再次治疗)。分别于术后1、3、6个月进行胃镜检查,评估内镜治疗后主要观察指标:曲张静脉止血成功率、技术成功率、根除率、复发率;次要指标(相关并发症):内镜治疗相关出血、发热、败血症和远处栓塞。结果EBL组和EVO组技术成功率、止血成功率、平均治疗次数、胃底静脉曲张根除率差异无统计学意义。EVO组复发率高于EBL组(P<0.05)。EBL组内镜治疗相关出血率低于EVO组,发热率低于EVO组(P<0.05);EVO组中1例患者在注射后发生肺栓塞,3例患者出现败血症。结论大容量套扎器与内镜下注射组织胶根除GOV型胃静脉曲张的短期疗效相似,但前者安全性优于后者。

关键词：食管和胃静脉曲张出血套扎疗法内窥镜检查组织胶

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Quality evaluation of land reclamation in mining area based on remote sensing

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International Journal of Coal Science & Technology 2023年第3期10卷 204-213页

作者： shidong Wang Jjianhua Guo Yang yu Pujie shi Hebing Zhang School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuoHenan 454000China China Institute of Geo-Environment Monitoring Beijing 100081China China Construction Seventh Bureau Urban Investment and Operation Management Co Zhengzhou 450000China

Several deficiencies exist in the present evaluation of land reclamation quality in mining *** include the absence of an established set of evaluation index systems and standard acceptance criteria,as well as the use of traditional sam-pling techniques,which are costly and in eficiency,and *** with the traditional sampling survey methods,remote sensing has the advantages of a wide detection range,diverse information collection,multiple data-acquiring strategies,high speed,and short *** this study,we used the Xinzhuang coal mining field in Yongcheng,Henan Province as an example to extract information and invert surface parameters using remote sensing techniques,based on national and local reclamation regulations and ***,using remote sensing,we constructed an index system for evaluating land reclamation quality in three aspects:reclaiming project quality,soil quality,and ecological *** the grading standards of evaluation indicators and quantitative remote sensing models,we determined the extracted information on the area of indicators,roads,ditches,soil moisture,organic matter,and ecological benefits after *** on this,we established a quality evaluation model for mining land reclamation using an improved index and *** evaluation units were divided,and the weight of the evaluation index was determined using the analytic hierarchy process and data envelopment analysis(AHP-DEA)*** land reclamation quality in the study area was comprehensively evaluated,field accuracy was verified,and the results were *** results show that,except for the removal of roads,houses,and fishponds in the study area,all 13 evaluation units achieved a score of 60 points or *** quality of reclamation met the standards,and the evaluation results were consistent with the conclusions of the field investigation and project acceptance report,demonstrating the reliability and feasibility of the m

关键词： Remote sensing Mining area land-Reclamation quality Evaluation Soil

Evaluation of underground blast-induced ground motions through nearsurface low-velocity geological layers

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 600-617页

作者： Yonggang Gou xiuzhi shi Zhi yu Xiaofeng Huo Xianyang Qiu College of Civil and Transportation Engineering Hohai UniversityNanjing210098China School of Resources and Safety Engineering Central South UniversityChangsha410083China Oulu Mining School University of OuluOuluFI-90014Finland

Surface ground motion produced by underground blasts is significantly influenced by near-surface geological ***,near-surface low-propagation velocity layers were always ignored in past analyses of ground motions due to their thin *** the rising concern about surface ground motions produced by the ascendant scale and frequentness of underground excavation and mining,close attention is gradually paid to ground blast ***,systemic experiments were conducted and took seven months in an underground mine to clarify the variation of motion from underground rock to surface *** attenuation of surface ground peak particle velocities(PPVs)is compared to that in underground rock,and horizontal amplitudes are compared to vertical *** between bedrock and surface ground vibrations are analyzed to illustrate the site effect of near-surface lower-propagation velocity ***-dimensional site response analysis is employed to quantify the influence of different geological profiles on surface ground *** experimental data and site response analysis allowed the following conclusions:(1)geological site effects mainly produce decreasing dominant frequency(DF)of surface ground vibrations;(2)the site amplification effect of blast vibration needs to be characterized by peak particle displacement(PPD);(3)shear waves(S-waves)begin to dominate and surface Rayleigh waves(R-waves)develop as blast-induced ground vibrations travel upward through rock and lower-velocity layers to the *** comparison of response relative displacement to a critical value is best to assess the potential for cracking on surface structures.

关键词： Surface ground motions Underground blasts Geological site condition Amplitude attenuation Site response analysis

天麻钩藤饮对AngⅡ诱导血管平滑肌细胞氧化应激中PINK1/Parkin通路的影响

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中国中药杂志 2024年第14期49卷 3894-3900页

作者：时拥月符雁榕秦钦陈雨丝姚佳梅钟广伟中南大学湘雅医院老年医学科湖南长沙410008 湖南师范大学医学院湖南长沙410006 中南大学湘雅医院国际医疗部湖南长沙410008 中南大学湘雅医院国家老年疾病临床医学研究中心湖南长沙410008

探讨天麻钩藤饮对血管紧张素Ⅱ(AngⅡ)诱导血管平滑肌细胞(VSMC)氧化应激的影响及其分子机制。采用组织贴块法进行原代大鼠血管平滑肌细胞培养,α-actin免疫细胞荧光法鉴定VSMC,AngⅡ1×10^(-6) mol·L^(-1)作为刺激因子,天麻钩藤饮灌胃... 详细信息

探讨天麻钩藤饮对血管紧张素Ⅱ(AngⅡ)诱导血管平滑肌细胞(VSMC)氧化应激的影响及其分子机制。采用组织贴块法进行原代大鼠血管平滑肌细胞培养,α-actin免疫细胞荧光法鉴定VSMC,AngⅡ1×10^(-6) mol·L^(-1)作为刺激因子,天麻钩藤饮灌胃Sprague Dawley(SD)大鼠制备药物血清;将大鼠VSMC分为正常组、模型组、中药组和抑制剂(3-甲基腺嘌呤,3-MA)组;cell counting kit-8(CKK-8)法检测细胞增殖活性,溴脱氧尿苷(BrdU)流式细胞仪检测细胞周期,Transwell实验检测细胞迁移能力;酶联免疫吸附实验(ELISA)检测VSMC中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和丙二醛(MDA)的活性;采用DCFH-DA荧光探针检测细胞内活性氧(ROS)荧光强度;采用蛋白免疫印迹(Western blot)检测VSMC中PTEN诱导假定激酶1(PTEN-induced putative kinase 1,PINK1)、帕金蛋白(Parkin)、p62及轻链3-Ⅱ(LC3-Ⅱ)蛋白表达。结果显示,天麻钩藤饮含药血清在8%质量分数下干预48 h后可显著抑制VSMC生长;与正常组比较,模型组细胞增殖活性及迁移数量明显增加,SOD、CAT含量显著降低,MDA含量显著升高,ROS荧光强度显著增强,PINK1、Parkin及LC3-Ⅱ蛋白表达显著下降,p62蛋白表达显著升高。与模型组比较,中药组VSMC增殖活性及迁移数量均明显降低,SOD、CAT含量显著增加,MDA含量显著下降,ROS荧光强度显著减弱,PINK1、Parkin及LC3-Ⅱ蛋白表达显著升高,p62蛋白表达显著下降。与中药组比较,加入线粒体自噬抑制剂3-MA可阻断天麻钩藤饮含药血清干预VSMC增殖迁移、线粒体自噬及氧化应激水平,差异具有统计学意义。综上所述,天麻钩藤饮具有良好的抗氧化活性,可抑制细胞增殖和迁移,其作用机制可能与激活线粒体自噬PINK1/Parkin信号通路有关。

关键词：天麻钩藤饮血管平滑肌细胞氧化应激线粒体自噬 PINK1/Parkin通路

Transient fuel performance analysis of UO_(2)–BeO fuel with composite SiC coated with Cr cladding based on multiphysics method

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Nuclear Science and Techniques 2023年第12期34卷 93-108页

作者： Chun‑yu Yin shi‑Xin Gao Sheng‑yu Liu Rong Liu Guang‑Hui Su Li‑Bo Qian School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China School of Electric Power South China University of TechnologyGuangzhou 510640China

The transient multiphysics models were updated in CAMPUS to evaluate the accident-tolerant fuel performance under accident *** is a fuel performance code developed based on *** simulated results of the UO_(2)–Zircaloy fuel performance under accident conditions were compared with those of the FRAPTRAN code and the experimental data to verify the correctness of the updated ***,multiphysics models of the UO_(2)–BeO fuel and composite SiC coated with Cr(SiC_(f)/SiC-Cr)cladding were implemented in ***,the fuel performance of the three types of fuel cladding systems under Loss of Coolant Accident(LOCA)and Reactivity Insertion Accident(RIA)conditions was evaluated and compared,including the temperature distribution,stress distribution,pressure evolution,and cladding failure *** results showed that the fuel temperature of the UO_(2) fuel under accident conditions without pre-irradiation was lower after being combined with SiC_(f)/SiC-Cr ***,the centerline and outer surface temperatures of the UO_(2)–BeO fuel combined with SiC_(f)/SiC-Cr cladding reduced further under accident *** cladding temperature increased after the combination with the SiC_(f)/SiC-Cr cladding under accident conditions with *** addition,the use of SiC_(f)/SiC-Cr cladding significantly reduced the cladding hoop strain and plenum pressure.

关键词： Accident condition Fuel performance UO2–BeO fuel SiCf/SiC-Cr cladding

Co-YPO_(4)双功能催化剂促进乙醇高值转化制丁二烯

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Chinese Journal of Catalysis 2024年第1期56卷 166-175页

作者：周百川李文翠王嘉孙丹卉向诗煜高新芊陆安慧大连理工大学化工学院辽宁省低碳资源高值化利用重点实验室精细化工国家重点实验室辽宁大连116024

丁二烯是重要的化工原料,主要用于生产树脂、合成橡胶、丁二醇和己二腈等大宗化学品,还可以用于制备蒽醌、四氢苯酐等精细化学品.目前,工业上制备丁二烯的方法主要是乙烯副产抽提法.近年来,随着生物乙醇技术大力发展,催化乙醇制丁二烯... 详细信息

丁二烯是重要的化工原料,主要用于生产树脂、合成橡胶、丁二醇和己二腈等大宗化学品,还可以用于制备蒽醌、四氢苯酐等精细化学品.目前,工业上制备丁二烯的方法主要是乙烯副产抽提法.近年来,随着生物乙醇技术大力发展,催化乙醇制丁二烯成为很有吸引力的生产丁二烯的路线之一.目前催化乙醇制丁二烯的催化剂种类较多,合理设计具有活性位点结构和功能的催化新材料是提升催化剂活性的关键.稀土金属元素如Y,La和Ce等具有独特的电子层结构,并且具有中等强度的Lewis酸性,本文尝试将稀土磷酸盐与具有乙醇脱氢活性的过渡金属位点结合起来,设计过渡金属改性的稀土磷酸盐催化剂并用于乙醇转化制丁二烯.本文开发了Co-YPO_(4)双功能催化剂,应用于乙醇转化制丁二烯反应,所制材料表现出较高的催化活性与稳定性.在YPO4催化剂上,乙醇主要发生脱水反应,生成大量的乙烯和乙醚,且丁二烯选择性不超过5%;而在Co-YPO_(4)催化剂上,乙醇转化产物分布出现明显改变,丁二烯选择性增加.在乙醇重时空速和反应温度分别为1.0 gC2H5OH×gCat.‒1×h^(‒1)和350℃的条件下,乙醇转化率为78.2%,丁二烯选择性为68.5%.原位紫外-可见漫反射光谱、X射线光电子能谱以及H_(2)^(-)程序升温还原表征结果表明,Co2+中心与PO_(4)^(3‒)基团存在强的配位相互作用,形成稳定且高度分散的[Co-O-P]物种.通过NH_(3)^(-)程序升温脱附(TPD)和吡啶探针分子吸附红外对YPO4和Co-YPO4进行酸性表征,结果表明,YPO_(4)和Co-YPO4表面均是典型的Lewis酸性位点;结合CO_(2)-TPD表征发现,Co^(2+)与YPO4表面部分Y3+位点发生置换,即引入适量的Co会减弱酸性同时增强表面碱性.进一步通过停留时间、乙醇程序升温表面反应和原位乙醇吸附反应漫反射红外光谱测试对反应机理进行详细研究.结果表明,乙醇首先在Co^(2+)位发生脱氢生成乙醛和H_(2),随后乙醛迁移至Y^(3+)位点吸附活化,两分子乙醛依次发生C‒C偶联、加氢以及脱水反应生成丁二烯.动力学测试结果表明,乙醇脱氢是整个反应过程的关键步骤,整体反应路径如下:乙醇→乙醛→丁烯醛→丁烯醇→丁二烯.综上所述,以乙醇作为平台分子合成丁二烯能够丰富可持续发展的新能源结构体系.本文揭示了磷酸根基团通过配位作用稳定Co^(2+)物种,Co^(2+)和Y^(3+)位点协同催化乙醇选择性生成丁二烯,为乙醇高值转化催化剂设计提供了新思路.

关键词：乙醇丁二烯脱氢碳碳偶联磷酸盐

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Chinese Physics Letters 2012年第4期29卷 206-209页

作者： LI yue DENG Ai-Hong ZHOU yu-Lu ZHOU Bing WANG Kang HOU Qing shi Li-Qun QIN xiu-Bo WANG Bao-Yi Department of Physics Sichuan UniversityChengdu 610064 Key Laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064 Institute of Modern Physics Fudan UniversityShanghai 200433 Laboratory of Nuclear Analysis Technique Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049

Various helium-containing titanium films were deposited on Si substrates by magnetron sputtering under different helium/argon (He/Ar) *** concentrations and corresponding depth profiles in the Ti films are obtained by elastic recoil detection analysis (ERDA).X-ray diffraction (XRD) measurements are carried out to evaluate the crystallization of the titanium ***-type defects and their depth profiles were revealed by slow positron beam analysis (SPBA).It is found that the defect-characteristic parameter S rises with the increment of the He/Ar flow *** variation of S indicates the formation and evolution of various Herelated defects,with uniform distribution into the depth around 400nm.

关键词： titanium Titanium increment

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行业特色高校学科专业的设置及调整优化

北京社会科学 2024年第9期 96-107页

作者：姚云孙士茹北京师范大学教育学部

学科调整优化布局直接影响到高校立德树人的成效和服务社会的能力与水平。采用案例分析法、访谈法和文本分析法,对东中西部14所行业特色高校学科专业设置的调研发现:高校学科系统向多科型转变,但结构水平欠佳;办学趋向综合化,但特色有... 详细信息

学科调整优化布局直接影响到高校立德树人的成效和服务社会的能力与水平。采用案例分析法、访谈法和文本分析法,对东中西部14所行业特色高校学科专业设置的调研发现:高校学科系统向多科型转变,但结构水平欠佳;办学趋向综合化,但特色有所削弱;主动对接地方需求调整学科专业,但风险管控不够。为凸显特色,坚守主业,行业特色高校须明确办学服务定位,采取“两面向两对标三路径”调整模式;加强质量内涵建设,提高学科专业设置饱和度;优化学科专业生态结构,加强特色学科地位与招生比重;创新组织制度设计,促进多学科交叉育人与联合技术攻关。

关键词：学科专业调整行业特色高校学科体系高等教育