检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

桥塔钢筋部品装配化建造技术的研究与应用

公路 2024年第5期69卷 128-133页

作者：董奇峰陈斌吴中正严双桥余昌文中交第二航务工程局有限公司武汉市430040 长大桥梁建设施工技术交通行业重点实验室武汉市430040 交通运输行业交通基础设施智能制造技术研发中心武汉市430040 中交公路长大桥建设国家工程研究中心有限公司武汉市430040

针对传统桥塔钢筋工程施工效率低、劳动强度大等问题,提出钢筋部品装配化建造成套技术,从部品化设计、工厂化生产和装配化施工3个方面依次展开研究。首先,对桥塔节段钢筋结构进行部品化拆分设计,通过对立体弯折钢筋网片结构的分析,提出... 详细信息

针对传统桥塔钢筋工程施工效率低、劳动强度大等问题,提出钢筋部品装配化建造成套技术,从部品化设计、工厂化生产和装配化施工3个方面依次展开研究。首先,对桥塔节段钢筋结构进行部品化拆分设计,通过对立体弯折钢筋网片结构的分析,提出了平面钢筋网片整体弯折成型的制作方法;其次,通过对钢筋网片各制作环节的分析,设计了自动化生产线的相应结构和配套的生产工艺,将钢筋网片进行工厂化生产,提高了钢筋网片的加工效率和成型质量;最后,结合工程特点,提出了保障钢筋部品装配化施工工艺和钢筋结构刚度的技术措施。工程建设应用表明,钢筋部品装配化建造成套技术取得了良好的应用效果,提高了桥塔钢筋加工精度和质量,同时减少了施工人数,降低了劳动强度,达到了预期的研发效果。

关键词：桥梁工程装配化建造钢筋网片整体弯折成型自动化生产线工厂化生产

Influence of MnO_2 Mineralizer on the Crystal Structure,Properties of SiC Kiln Furniture Bonded with Fine Silicon Powder

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 1997年第5期16卷 397-402页

作者： ruan yu-zhong wu Wan-Guo yu yan ZHAN Hong-Bing LIN Chun-Ying(Department of Chemlcal Engineering, Fuzhou University, 350002) Department of Chemical Engineering Fuzhou University 350002 China

The properties of SiC kiln furniture bonded with fine silicon powderare related to the bonder’s crystal structure. At high temperature, it will crystallize ina-cristobalite with great bulk effect. MnO2 mineralizer can make a-cristobalite convertto a-tridymite whose bulk effect is small. The crystal structure and its amount were investigated with XRD technique. The influence of different amounts of MnO2 on thecrystal structure and polycrystal transformation, and that of crystal structure on theproperties of kiln furniture were studied. The best proportion of MnO2 added was determined to be 2.0%.

关键词： MnO_2 mineralizer fine silicon powder SiC kiln furniture

Reversible on-off switching of spin-crossover behavior via photochemical [2+2] cycloaddition reaction

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2022年第1期65卷 120-127页

作者： Long-Fei Wang Bang-Heng Lv Feng-Tai wu Guo-Zhang Huang Ze-yu ruan yan-Cong Chen Min Liu Zhao-ping Ni Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou 510006China School of Nuclear Science and Technology University of South ChinaHengyang 421001China

Herein,we report the first example showing the reversible on-off switching of spin-crossover(SCO)property by solid state photochemical[2+2]*** ultraviolet(UV)light-induced[2+2]cycloaddition reaction of 3-spy ligands in a twodimensional(2D)Hofmann-type framework[Fe(3-spy)_(2){Pd(CN)_(4)}](1,3-spy=3-styrylpyridine),which shows a hysteretic twostep SCO behavior,gives a 3D Hofmann-type framework[Fe(rctt-3-ppcb){Pd(CN)_(4)}](2,rctt-3-ppcb=rctt-1,3-bis(3-pyridyl)-2,4-bis(phenyl)cyclobutane,r=reference group,c=cis and t=trans)accompanied with the disappearing of SCO ***,upon heating at 250℃ for 12 h,the rctt-3-ppcb ligand in 2 could be partially dedimerized to 3-spy with 68%completion through single-crystal-to-single-crystal(SCSC)transformation,giving the annealing complexes[Fe(3-spy)1.36(rctt-3-ppcb)0.32{Pd(CN)_(4)}](3)which display an incomplete SCO *** 2■3 interconversion is successfully achieved via continuous UV irradiation and thermal annealing,demonstrating the effectiveness of photochemical[2+2]reaction on switching on-off SCO properties.

关键词： reversible photo cycloaddition spin-crossover Hofmann-type frameworks photomagnetism

番茄果胶裂解酶基因SlPL参与调控裂果机制研究

在线全文

学校读者我要写书评

暂无评论

园艺学报 2024年第2期51卷 295-308页

作者：仲钊江吴震周蓉朱为民杨学东于筱薇徐艳高扬杨蒋芳玲南京农业大学园艺学院南京210095 上海市农业科学院园艺研究所上海201403

以裂果率差异极显著的番茄为材料,分析了SlPL(Solyc03g111690)基因的表达差异,进一步利用基因遗传转化对其进行功能验证。结果表明,SlPL在易裂番茄‘NT189’中的表达量显著高于耐裂番茄‘NT91’;在番茄果实中的表达量显著高于根、茎、... 详细信息

以裂果率差异极显著的番茄为材料,分析了SlPL(Solyc03g111690)基因的表达差异,进一步利用基因遗传转化对其进行功能验证。结果表明,SlPL在易裂番茄‘NT189’中的表达量显著高于耐裂番茄‘NT91’;在番茄果实中的表达量显著高于根、茎、叶、花等器官,且在果实转色期和红熟期表达量较高;通过灌水处理和ABA处理诱导果实开裂,发现在相同处理时期,易裂果材料果实中SlPL表达量总体显著高于耐裂果材料。通过遗传转化获得SlPL过表达(OEPL)和敲除(pl)的株系,与野生型相比,OEPL更易裂果,且果实硬度显著降低,pl果实硬度升高。OEPL果实中原果胶含量显著低于野生型,水溶性果胶含量显著高于野生型,pl果实中原果胶和总果胶含量显著高于野生型;OEPL果实中果胶裂解酶活性显著高于野生型,pl果实中果胶裂解酶活性显著低于野生型。基因表达分析发现,OEPL果实中细胞壁代谢相关基因SlPG2、SlPME2.1、SlCel2、SlGH9C5和乙烯合成途径相关基因SlACS4、SlACO1的相对表达量显著高于野生型,pl果实中则相反。pl果实中乙烯响应因子SlERF2的相对表达量显著高于野生型。果皮显微结构观察发现,与野生型相比,OEPL表皮层细胞和薄壁细胞排列稀疏,而pl果皮细胞排列更为紧密。

关键词：番茄裂果 SlPL 功能验证

Sonographic evaluation of vessel grafts in living donor liver transplantation recipients of the right lobe

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第28期15卷 3550-3554页

作者： Qiang Lu Hong wu yu-Ting Fan yan Luo zhong-Wei Zhang Department of Sonography West China Hospital Sichuan University Chengdu 610041China Liver Transplantation Center West China Hospital Sichuan University Chengdu 610041China

AIM： To evaluate the vessel grafts （VG） used to reconstruct the middle hepatic vein （MHV） tributaries with ultrasonography. METHODS： Twenty-four patients undergone living donor liver transplantation were enrolled in our study. MHV tributaries larger than 5 mm in diameter were reconstructed with interposition VG. Blood flow of the graft and interposition VG was checked by Doppler ultrasonography daily in the first 2 postoperative weeks and monthly followed up after discharge. The sensitivity of VG detected by ultrasonography was assessed using surgical records as references. Student＇s t test was used to compare the velocity of VG and occluded VG in chronic patents （〉 3 mo）. RESULTS： Thirty-one VG were used to reconstruct the MHV tributaries. Ultrasonography identified 96.7% （30/31） of large MHV tributaries and 90.3% （28/31） of VG. The diameter of VG was 5.6 ± 0.8 mm and the velocity of VG was 19.7 ± 8.1 cm/s. Two VG （2/31, 6.5%） were occluded on the first postoperative day in one patient who suffered from persistent ascites and had a prolonged recovery of liver function. Twenty-six VG （26/31, 83.9%） were patent 2 wk after operation. Six （6/31, 19.4%） VG were patent over 3 mo after operation. Intrahepatic venous collaterals were detected in 29.2% （7/24） patients. The velocity of VG and occluded VG was 30.1 ± 5.6 cm/s, 16.5 ± 5.8 cm/s, respectively, in chronic patents. The difference between two groups was statistically significant （P 〈 0.001）. CONCLUSION： Our results indicate that most VG are patent in the first postoperative week while only a small portion with a higher velocity remains patent after 3 mo. Intrahepatic venous collaterals can be observed in some patients after occlusion of VG.

关键词： Living donor liver transplantation Ultrasound Vessel graft Venous collateral Middle hepaticvein

Long non-coding RNA: The functional regulator of mesenchymal stem cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2019年第3期11卷 167-179页

作者： zhong-yu Xie Peng Wang yan-Feng wu Hui-Yong Shen Department of Orthopedics The Eighth Affiliated Hospital Sun Yat-sen University Center for Biotherapy Sun Yat-sen Memorial Hospital Sun Yat-sen University

Mesenchymal stem cells(MSCs) are a subset of multipotent stroma cells residing in various tissues of the body. Apart from supporting the hematopoietic stem cell niche, MSCs possess strong immunoregulatory ability and multiple differentiation potentials. These powerful capacities allow the extensive application of MSCs in clinical practice as an effective treatment for ***, illuminating the functional mechanism of MSCs will help to improve their curative effect and promote their clinical use. Long noncoding RNA(LncRNA) is a novel class of noncoding RNA longer than 200 nt. Recently,multiple studies have demonstrated that LncRNA is widely involved in growth and development through controlling the fate of cells, including MSCs. In this review, we highlight the role of LncRNA in regulating the functions of MSCs and discuss their participation in the pathogenesis of diseases and clinical use in diagnosis and treatment.

关键词： Mesenchymal stem cells Long non-coding RNA Regulator Multipotent stroma cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

利用含铝废渣合成的堇青石结构表征(英文)

人工晶体学报 2007年第5期36卷 1091-1095页

作者：吴任平阮玉忠于岩福州大学材料科学与工程学院福州350002

采用铝型材厂工业废渣,滑石粉和粘土为主要原料合成堇青石材料,用XRD和SEM法表征各样品的晶相结构和显微结构;用Rietveld Quantification内标半定量法确定各晶相的含量;用Philips X'pert plus软件确定各晶相的晶胞参数。实验结果表明:... 详细信息

采用铝型材厂工业废渣,滑石粉和粘土为主要原料合成堇青石材料,用XRD和SEM法表征各样品的晶相结构和显微结构;用Rietveld Quantification内标半定量法确定各晶相的含量;用Philips X'pert plus软件确定各晶相的晶胞参数。实验结果表明:除晶胞参数发生微小变化外,合成的堇青石结构与单晶相同,属六方晶系,p6/mcc空间群;除堇青石相外,体系内还出现莫来石固溶体相和镁铝尖晶石相,他们的含量和晶胞参数也相应的进行了表征。

关键词：合成铝废渣堇青石晶相结构

K_2O杂质对铝型材厂工业废渣合成的堇青石材料晶相结构的影响

在线全文

学校读者我要写书评

暂无评论

材料科学与工艺 2008年第1期16卷 125-127页

作者：于岩阮玉忠吴任平福州大学新校区材料学院福建福州350108

主要探讨K2O杂质对堇青石形成及晶相结构的影响.采用XRD和SEM确定各试样的晶相结构和显微结构.实验结果表明：K2O杂质含量从0.23～1.1wt%,形成的堇青石晶相量较多,其中K2O杂质含量为1.1wt%时,堇青石含量高达90%,当K2O含量继续增加时,形... 详细信息

主要探讨K2O杂质对堇青石形成及晶相结构的影响.采用XRD和SEM确定各试样的晶相结构和显微结构.实验结果表明：K2O杂质含量从0.23～1.1wt%,形成的堇青石晶相量较多,其中K2O杂质含量为1.1wt%时,堇青石含量高达90%,当K2O含量继续增加时,形成的堇青石量开始减少,确定试样中K2O杂质最高允许含量为1.1wt%.plus软件分析结果：K2O杂质对堇青石的晶胞结构影响不大,晶胞参数变化很小.

关键词：工业废渣堇青石杂质晶相结构

型壳温度对DZ22B合金叶片枝晶组织的影响

在线全文

学校读者我要写书评

暂无评论

铸造 2024年第4期73卷 489-497页

作者：钟文惠丁鹏飞谢维封举宁王鑫铭吴煜刘艳中国航发南方工业有限公司湖南株洲412000 湘潭大学材料设计及制备技术湖南省重点实验室湖南湘潭411105 湘潭大学材料科学与工程学院湖南湘潭411105

以DZ22B镍基高温合金叶片为研究对象,采用ProCAST数值模拟及试验相结合的方法对不同型壳保温温度下铸造叶片定向凝固过程中的温度场、热裂倾向及组织进行研究。结果表明:随着型壳保温温度的增加,等温线整体呈下凹趋势,处于1 540℃温度... 详细信息

以DZ22B镍基高温合金叶片为研究对象,采用ProCAST数值模拟及试验相结合的方法对不同型壳保温温度下铸造叶片定向凝固过程中的温度场、热裂倾向及组织进行研究。结果表明:随着型壳保温温度的增加,等温线整体呈下凹趋势,处于1 540℃温度下的糊状区下凹程度明显大于其他温度,且叶片HTI结果有所增加,容易产生热裂的区域集中在叶身上部,排气边位置容易产生热裂的区域比进气边更大;相同高度位置下的叶片排气边枝晶间距均小于进气边枝晶间距;随型壳保温温度升高,一次枝晶间距和二次枝晶间距均降低,对比模拟结果与试验统计得出的一次枝晶间距和二次枝晶间距,得出一致结论,模拟与试验吻合较好。

关键词： DZ22B高温合金定向凝固枝晶组织型壳温度数值模拟

维普期刊数据库博看期刊