Association of solid fuel use with risk of stunting in children living in China

Stunting adversely affects physical and mental outcomes of children. It has not been examined whether household air pollution from solid fuel combustion is a risk factor for stunting in children. In a total of 41,439 children aged 6-17 across China, height was measured using a unified protocol. Multivariable linear regression models and logistic regression models were used to assess the associations of solid fuel use for cooking/heating with stunting in children. Adjusted for covariates, cooking/heating with solid fuel was significantly associated with a lower z-score for height for age and sex (β = −0.21 [−0.32 to −0.09] and −0.17 [−0.31 to −0.03], respectively) and an increased risk of stunting with an estimated ORs of 1.34 [1.07~1.68] and 1.37 [1.02~1.83], respectively. The risk of stunting associated with solid fuel use was statistically significant in high-age children. And the effect was greater on girls than on boys, though the difference was not statistically significant. Our study suggested that Chinese children living in households using solid fuel had a significantly higher risk of stunting than those living in households using cleaner fuel.     

装备知识管理效用及实施策略分析

知识军事时代，知识逐渐成为战斗力提升的核心要素。武器装备的知识化管理，即装备知识管理，作为一种新的管理理念逐渐引起人们的重视，并将成为武器装备管理发展的新趋势。从探讨装备领域实施知识管理（knowledge management，KM）的重要性及目前装备工作中存在的现实问题出发，从提高装备决策质量、提升装备人才工作能力、防止装备知识流失、促进装备知识传递等方面分析了实施装备知识管理可能产生的效用。同时，还分析了装备知识管理实施的基本策略，以此为基础概括出了装备知识管理具有操作意义的实施步骤。     

Plasma Sprayed Hydroxyapatite Coatings with Nano-hydroxyapatite Prepared by Ultrasonic Precipitation Process

Nano-particle hydroxyapatite （ HA ） was prepared with a novel ultrasonic precipitation process and the as-prepared nanopowder was used to produce hydroxyapatite （ HA ） coatings on titanium substrate via plasma spraying. The phase and the microstructare of the coating were characterized by X- ray diffraction （XRD） and scanning electron microscopy （SEM）. Results showed that spherical particles could be prepared by ultrasonic precipitation process; and a corresponding dense HA coating with molten surface and low-porosity cross-section structure was acquired. During the plasma spraying process, new phases of Ca3 （ PO4 ）2 and Ca2 P2O7 were generated. After heat-treating at 800℃ for 1 h, the contents of Ca3 （ PO4 ）2 and Ca2 P2O7 decreased while HA content increased. Tensile adhesion tests showed that the plasma sprayed coating prepared with the spherical nanoparticles exhibited high tensile bond strength.     

粘钢技术在输水管竖井加固中的应用

１９７６年汛前发现响水潭水库输水管竖井圆筒底部与闸室连接处的下游出现环形水平裂缝，对此当年曾加固处理。１９８６年复查时，发现竖井原处又出现了类似的环形裂缝，并有新的发展，为确保工程安全，于１９９４年３月再次加固。此次加固采用先止水，后粘钢板的加固方法，收到很好的效果。     

Cr12钢的预处理工艺研究

本文研究了Ｃｒ１２钢经４种不同的预处理工艺处理后钢中碳化物的大小，数量，分布及钢的硬度，强度和韧性，试验结果表明，经调质处理，高温固溶淬火＋高温退火处理后，Ｃｒ１２钢中碳化物的大小，分布及其组织，性能均优于常规球化退火预处理的。通过扫描电镜对冲击断口的分析，初步探讨了新的预处理工艺提高韧性的原因。     

亲电聚合路线合成聚醚醚酮酮砜的研究

用4,4′-二苯氧基二苯砜(DPODPS)分别与对苯二甲酰氯(TPC)、间苯二甲酰氯(IPC)或2,5-二氯对苯二甲酰氯(DCC)在1,2-二氯乙烷(DCE)中,以无水 AlCl_3为催化剂,在 N-甲基吡咯烷酮(NMP)存在下,通过付-克亲电聚合反应,制得了五种不同结构的聚醚醚酮酮砜(简称PEEKKS)。用红外光谱(IR)、X-射线衍射(XRD)、扫描电镜(SEM)、差示扫描量热(DSC)、热重(TG)及耐溶剂试验,对聚合物进行了表征。结果表明,五种聚合物的对数比浓粘度(η_(inh))均达到0.85以上.具有较低的熔融温度、良好的溶解性能和耐高温性能,PEEKKS 属于非晶态聚合物。     

用正交设计法优化导叶分段关闭规律的参数

本文介绍了正交设计法优化水轮机导叶分段关闭规律参数的方法，实例表明，此方法具有简单，准确和直观的优点。