涡轮发动机喷气燃料低温性和贮存性改善研究

导弹用涡轮发动机采用的喷气燃料要求具有良好的耐低温性能和贮存性能。文中介绍了工程应用领域中通过对普通燃料脱水、脱氧精制成的一种低温性和贮存性都较优的油封燃料,该项措施在国内相关领域具有一定的创新性。     

自然贮存条件下发动机的性能变化

桌发动机在南、北方自然环境条件下贮存了1～3a,发动机各零部组件与零状态相比差异不大,随发动机一起贮存的药柱方坯力学性能有所下降。对发动机在南、北方自然贮存环境下的变化情况进行了描述,就推进剂方坯力学性能下降情况进行了分析。     

制导弹药火工品单应力水平加速寿命试验研究

准确判定火工品的剩余寿命,对制导弹药维修工作至关重要。从制导弹药储存的实际情况出发,阐述了适时对火工品实施加速寿命试验的必要性,分析了加速寿命试验中的加速应力、寿命分布、加速系数、应力水平和试验时间,最后结合火工品具有一定储存期和试验为单一应力水平的特点,从不同角度对试验数据处理进行了探讨,从而得出了更为准确的试验结果。     

基于HSI 模型的印度洋大眼金枪鱼栖息地研究

根据日本商业性金枪鱼延绳钓生产数据,应用栖息地指数模型(HSI)和地理信息系统(GIS)图形显示技术对印度洋大眼金枪鱼的栖息地分布进行研究.研究结果表明:印度洋大眼金枪鱼最适合栖息的海域主要集中在70°E以东,15°S以北印度洋海域,栖息地指数值在0.75～1.00;而20°E～50°E,30°S～40°S海域以及65°E～120°E,20°S～40°S之间大部分海域的大眼金枪鱼HSI指数集中在0.25～0.50之间;其余海域的大眼金枪鱼HSI指数均分布在0.50～0.75之间.     

Methane emissions during storage of different treatments from cattle manure in Tianjin

Many studies on methane emissions from animal manure have revealed that animal manure is a major source of methane emissions to the atmosphere that can have negative consequences for people,animals and environment.In general,the release of methane can be influenced by the type of feed taken by animals,temperature,manure characteristics and so on.This study aimed at quantifying and comparing methane release from dairy manure with different piling treatments.Four treatments were designed including manure piling height 30,45,60 cm and adding 6 cm manure every day until the piling height was 60 cm.Static chamber method and gas chromatography were adopted to measure the methane emissions from April to June in 2009.Methane emission rates of all four manure treatments were low in the first week and then increased sharply until reaching the peak values.Subsequently,all the methane emission rates decreased and fluctuated within the steady range till the end of the experiment.Wilcoxon nonparametric tests analysis indicated that methane emission rate was greatly influenced by manure piling height and manner.There were no significant relationships between methane emission rates and the temperatures of ambience and heap.However,regression analysis showed that the quadratic equations were found between emission rates of all treatments and the gas temperature in the barrels.     

热重点斜法快速评估氟硅橡胶贮存寿命

阐述了热重点斜法（TPS）的基本原理。利用热重分析法求算出氟硅橡胶的功能性活化能E,同时开展373.15 K下热空气老化试验,然后参照JB/T 1544-1999计算氟硅橡胶贮存寿命,并对热重点斜法提出了分析和讨论。     

调蓄池在排水系统中的研究进展

城市排水系统是城市非常重要的一个组成部分。中国大部分城市的旧城区采用的是合流制排水系统,新建区域则多规划采用分流制排水系统,调蓄池在各排水系统中起着重要的作用。本文探讨了调蓄池在国内外的发展、调蓄池的功能及设计方法,并介绍了中国调蓄池的研究及应用状况,指出调蓄池可有效削减排水系统雨季污水排放量,并改善排放水质,从而改善了城市水体环境。文章最后对调蓄池的未来研究方向进行了展望。     

纯化方式和保存条件对改性落叶松单宁絮凝性的影响

选择一种典型植物多酚——落叶松单宁,研究了纯化方式和保存条件对改性植物多酚絮凝性的影响,通过测定相对黏度和红外谱图分析稳定性变化的原因.对于1 g.L-1的高岭土模拟水样,未纯化落叶松单宁改性后的最佳投加量为10 mg.L-1;经过抽滤、萃取、离心后的纯化样,改性后最佳投加量降低到1 mg.L-1,且以液体或固体形式在4℃或25℃条件下保存30 d后仍具有较好絮凝性;而只经抽滤、离心,未经萃取的纯化样,其改性产物只有保存于4℃才有絮凝性;只经抽滤、萃取,未经离心或只经抽滤的纯化样,对应改性产物只有以固体形式在4℃保存才有絮凝性.以4℃保存的固体样相对黏度变化最小,且相对黏度的变化越小,絮凝性能的稳定性越强.红外结果显示,落叶松单宁中含有大量的酚羟基基团,改性后,叔胺基团加成到芳环上,但保存前后红外谱图变化不大.     

1987-2008年南四湖湿地植被碳储量时空变化特征

利用研究区1987、1997和2008年的LandsatTM／ETM＋卫星遥感数据,结合实地采样调查和收集的资料,计算3个时期山东省南四湖湿地各植被类型的面积和碳储量;同时依照不同覆被类型（植被类型）的平均碳储量将各覆被类型的斑块划分为不同储碳等级,绘制3个时期的南四湖湿地植被碳格局图,分析植被碳储量的时空变化特征、变化产生的原因和变化对湿地的潜在影响。研究结果表明：研究前期（1987年）植被储碳格局存在着明显的植被碳储量以湖南北中心线向两岸增大的带状特征,研究中后期（1997-2008年）带状储碳格局不断破碎化并最终消失。整个研究期高储碳等级的斑块面积不断减小,低储碳等级的斑块面积增加。湿地植被碳储量呈现前期基本稳定后期显著减少的特征,1987、1997和2008年湿地植被碳储量均值分别为1．07、1．08和O．64TgC,1987-1997年湿地植被碳储量平均年增加0．001TgC,变化幅度不大;1997-2008年年减少0．04TgC,下降较明显。其中自然植被碳储量在整个研究期内持续减少,人工植被碳储量呈现先增加后减少的波动变化特征,分析认为这一变化特征产生的主要原因是南四湖地区多因子驱动的土地覆被变化活动。通过区域湿地植被的碳平衡动态分析认为,植被碳储量（碳库）的减少可能会导致整个湿地碳储量的入不敷出,使整个湿地碳汇能力下降甚至可能变为碳源。     

Safeguarding Biodiversity and Ecosystem Services in the Little Karoo,South Africa

Abstract: Global declines in biodiversity and the widespread degradation of ecosystem services have led to urgent calls to safeguard both. Responses to this urgency include calls to integrate the needs of ecosystem services and biodiversity into the design of conservation interventions. The benefits of such integration are purported to include improvements in the justification and resources available for these interventions. Nevertheless, additional costs and potential trade‐offs remain poorly understood in the design of interventions that seek to conserve biodiversity and ecosystem services. We sought to investigate the synergies and trade‐offs in safeguarding ecosystem services and biodiversity in South Africa's Little Karoo. We used data on three ecosystem services—carbon storage, water recharge, and fodder provision—and data on biodiversity to examine several conservation planning scenarios. First, we investigated the amount of each ecosystem service captured incidentally by a conservation plan to meet targets for biodiversity only while minimizing opportunity costs. We then examined the costs of adding targets for ecosystem services into this conservation plan. Finally, we explored trade‐offs between biodiversity and ecosystem service targets at a fixed cost. At least 30% of each ecosystem service was captured incidentally when all of biodiversity targets were met. By including data on ecosystem services, we increased the amount of services captured by at least 20% for all three services without additional costs. When biodiversity targets were reduced by 8%, an extra 40% of fodder provision and water recharge were obtained and 58% of carbon could be captured for the same cost. The opportunity cost (in terms of forgone production) of safeguarding 100% of the biodiversity targets was about US$500 million. Our results showed that with a small decrease in biodiversity target achievement, substantial gains for the conservation of ecosystem services can be achieved within our biodiversity priority areas for no extra cost.