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Microstructure of Fe-Based Alloy Hardfacing Coating Reinforced by TiC-VC Particles

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Journal of Iron and Steel Research International 2006年第4期13卷 51-55页

作者： wang xin-hong ZOU zeng-da QU Shi-yao School of Materials Science and Engineering Shandong University Jinan 250061 Shandong China

Mierostrueture of the Fe-based alloy hardfaeing coating reinforced by TiC-VC particles was investigated by means of SEM, TEM, XRD and EPMA. The thermodynamics and effect of elements on the carbides were discussed. The result shows that TiC-VC carbides can be formed during arc welding. Carbides with particle size of 2 ～4μm are uniformly dispersed in the matrix. Evidently the covering components and their amount affect the microstrueture and hardness of the coatings. An excellent microstructure and hardness of hardfacing coating were obtained, while the amount of graphite, FeTi and FeV was controlled within the range of 8%- 10%, 15%- 18% and 8%- 12%, respectively.

关键词： TiC-VC particle arc welding Fe-based hardfacing coating microstructure

A RAPID AND EFFECTIVE METHOD FOR THE DEACYLATION OF 1,4-DIACETYL-2,5-PIPERAZINEDIONE AND ITS DERIVATIVES

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Chinese Chemical Letters 1993年第8期4卷 687-688页

作者： Li xin wang Yao zeng SHI zeng Ming DU Hong Wen HU Department of Chemistry,Nanjing University 210008,Nanjing

A concise while effective method for the deacylation of 1,4-diacetyl-2,5-piperazinedione and its derivatives is supplied.

关键词： PDO ITS

Changes of nitric oxide synthase and cyclic guanosine mono-phosphate in form deprivation myopia in guinea pigs

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Chinese Medical Journal 2007年第24期120卷 2238-2244页

作者： WU Jie LIU Qiong YANG Xiao YANG Hui wang xin-mei zeng Jun-wen State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Centre Sun Yat-sen University Guangzhou 510060 China

Background The form deprivation （FD） reduces spatial contrasts and induces myopia. Nitric oxide and cyclic guanosine monophosphate （cGMP） are involved in visual signal transmission. This study investigated changes in nitric oxide synthase （NOS） activity and cGMP concentration in ocular tissues in acute and chronic form deprivation myopia. Methods Guinea pigs had one eye covered by translucent glass for 7, 14 or 21 days. Untreated litter mates were used as controls. NOS activity and cGMP concentrations in the retinal, choroidal and scleral tissues of FD eyes and control eyes were analyzed by radioimmunoassay after various durations of FD. The expression of NOS subtypes was identified by immunohistochemistry. Results Myopia was successfully induced in FD eyes after 14 days. Compared with control groups, the retinal NOS activity and cGMP concentrations in the FD eyes significantly increased after 14 and 21 days while the retinal NOS activity in the FD eyes was transiently suppressed by 7 days of FD. The NOS activity and cGMP concentrations of choroid and sclera in the FD eyes were higher than in the control groups at 21 days. The three isoenzymes of nitric oxide synthase were detected in the ocular tissues of guinea pigs. Conclusions The NOS activity and cGMP concentrations were upregulated after chronic FD and the retinal NOS activity was transiently suppressed at acute FD. The function of elevated NOS activity may be mediated by cGMP.

关键词： cyclic GMP growth guinea pigs myopia nitric oxide synthase

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生活小区换热站节能自动化技术应用

给水排水 2008年第9期34卷 115-116页

作者：王增欣平顶山工学院建筑环境与热能工程系平顶山467000

为实现生活小区换热站节能和节水的目标,在分析换热站运行工况的基础上,采用了质调、量调相结合的供热模式。通过将自动调节技术和变频调速技术应用于换热站系统设计,得到了一种自动化程度高、调节精度高、节水节能的生活小区换热站控... 详细信息

为实现生活小区换热站节能和节水的目标,在分析换热站运行工况的基础上,采用了质调、量调相结合的供热模式。通过将自动调节技术和变频调速技术应用于换热站系统设计,得到了一种自动化程度高、调节精度高、节水节能的生活小区换热站控制方案。

关键词：换热站变频器节能自动化

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基于有序聚类法的土壤水分剖面划分

西北农林科技大学学报（自然科学版） 2011年第2期39卷 191-196,201页

作者：王信增焦峰西北农林科技大学资源环境学院陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100

【目的】研究有序聚类法在土壤水分剖面划分中的应用。【方法】在黄土高原丘陵区陕西省安塞县,以乔木林地、灌木林地、果园用地和天然草地等4种土地利用类型为研究对象,测定4种用地类型0-500 cm土层（每20 cm为1层,共25层）的土壤水分含... 详细信息

【目的】研究有序聚类法在土壤水分剖面划分中的应用。【方法】在黄土高原丘陵区陕西省安塞县,以乔木林地、灌木林地、果园用地和天然草地等4种土地利用类型为研究对象,测定4种用地类型0-500 cm土层（每20 cm为1层,共25层）的土壤水分含量,然后采用有序聚类法对4种土地利用类型土壤水分剖面进行分层。【结果】从专业角度无法确定最优分类数K时,可以利用碎石图来确定,对全部样本进行分类并作碎石图可知,当K=4时,有序分割达到最优;对土地利用类型而言,土壤水分剖面总体可划分为水分弱利用层、根系集中层、强烈耗水层、水分调节层等4层,中间2层又可简单地归结为土壤水分利用层。【结论】基于有序聚类法划分的土壤水分剖面分层结果符合黄土高原丘陵沟壑区的土壤水分垂直分布实际,表明了该分层方法的合理性。

关键词：黄土丘陵区有序分类法土壤水分分层