黑龙江黑河大新屯金矿区地质特征及成因机理初探

大新屯金矿区位于多宝山一大新屯整装勘查带上,矿体产于新元古代北宽河组地层,矿体赋存于北西向断裂内;地球化学Au、Ag、As、Sb、Hg低温元素浓集中心发育,元素套合叠合程度较高,异常北西向带状展布;开展的激电中梯异常显示低阻高极化特点,极化率异常与土壤化探异常展布方向及矿体产出位置较一致,钻孔查证表明激电测深高极化率异常与矿体深部产出位置吻合。花岗质及中性闪长质岩浆的上侵为矿体的形成提供了充足的热源。由于矿脉与岩浆之间存在着较为密切的时空关系,得出矿床为老地层＋构造＋岩浆的成矿规律。     

穿透曲线法获取固定床吸附器的传质扩散系数

研究了煤质活性炭对不同浓度苯酚溶液的吸附，应用固定床吸附动力学模型、非线性回归固定床吸附流出曲线数据，获得了酚类在活性炭上的扩散传质系数。结果发现，酚类的表面扩散系数ＤＳ强烈地依赖于入口酚的浓度，随着酚浓度的升高，表面扩散系数增大。采用上述扩散系数理论预测了其他操作条件下的流出曲线，结果表明实验曲线与预测曲线相符甚好，穿透曲线法能可靠地获取液固吸附过程的吸附扩散系数，为吸附工程设计提供有益的帮助     

滑片膨胀机滑片摩擦损失的理论分析及实验验证

滑片膨胀机内滑片与转子及气缸之间的摩擦损失是影响滑片膨胀机热力性能的重要因素.建立了滑片膨胀机内滑片动力学模型,对滑片运动引起的摩擦损失进行了计算,并对计算结果进行了试验验证.研究结果表明:在1 000r/min的设计工况下,滑片槽底部安装有弹簧的滑片产生的摩擦功为80 W,该摩擦使得膨胀机的绝热效率降低20%.去掉弹簧后的滑片摩擦功减少了68.3%,但会导致滑片顶部脱离气缸,从而使高压气体大量泄漏.通过进一步对滑片膨胀机的结构参数进行了优化,寻找在保证滑片顶部与气缸的贴合紧密的前提下降低摩擦损失的台理方案.研究发现:增加滑片质量,滑片槽底部充适当压力气体,以及降低气缸内圆轮廓型线的偏心率都可以确保滑片顶部与气缸贴合紧密并且有效降低摩擦损失.3种优化方案可以分别将摩擦损失降低到现有样机的64.3%,36.5%和25.9%.     

Effect of pre rigor stretching on beef tenderness development

The objective of this study was to determine effects of pre rigor stretching on beef tenderness development. Beef loins (M. longissimus dorsi; n=24) were assigned to either stretching or non-stretching treatments and aged for 14days at -1.5°C. Sarcomere length, shear force, water-holding capacity and proteolysis were determined for the loins at 1, 7 and 14days of ageing. Stretching increased the length of the loins by 33% resulting in a trend of increasing sarcomere length (P=0.19). However, no significant differences for shear force values, purge, drip and cooking losses between treatments were found. Shear force values decreased with ageing times (P<0.05). Western blot assay found that stretching did not affect the extent of desmin degradation. The findings from the present study suggest that pre rigor stretching with the current increase in length will not contribute to tenderness improvement of the beef loins.     

发酵及添加鸡脂肪对鹿肉干营养特性和风味的影响

为改善传统发酵鹿肉干品质和风味的缺陷,向复配发酵剂（无戊糖片球菌:木糖葡萄球菌:植物乳杆菌=2:2:1）发酵的鹿肉干加入一定量的鸡脂肪,比较不发酵不加脂、发酵不加脂和发酵加脂三组鹿肉干的营养特性和风味的差异。结果表明:通过感官综合分析鸡脂肪最佳添加量为2%;发酵加脂组和不发酵不加脂组L*值分别为20.13和19.67,无显著性差异（P > 0.05）,但a*值（7.73）和b*值（9.29）值都显著高于不发酵不加脂组a*值（1.58）和b*值（2.34）（P<0.05）;发酵加脂组的水分含量（15.22%）和不发酵不加脂组（21.33%）显著高于发酵不加脂组（14.1%）（P<0.05）;发酵加脂组pH（5.04）显著（P<0.05）低于不发酵不加脂组pH（5.89）和发酵不加脂组pH（5.28）;发酵加脂组硬度（5071.22%）显著（P<0.05）低于不发酵不加脂组硬度（21143.94%）和发酵不加脂组硬度（10324.73%）;发酵加脂组脂肪酸（7.229 mg/100 g）比不发酵不加脂组脂肪酸（2.635 mg/100 g）和发酵不加脂组脂肪酸（3.591 mg/100 g）显著增加（P<0.05）;发酵加脂组氨基酸（12.218%）比不发酵不加脂组氨基酸（8.43%）和发酵不加脂组氨基酸（10.213%）显著增加（P<0.05）;发酵不加脂组和发酵加脂组挥发性物质中烯烃类相对含量分别为66.06%和55.85%,差异显著（P<0.05）,醛类、酸类、烷烃类含量显著相比,增加（P<0.05）,而醇类和杂环化合物含量显著减少（P<0.05）;综上,发酵及定量的鸡脂肪的添加对发酵鹿肉干的品质有积极影响,更加突出了发酵鹿肉干的营养特性和风味。     

脱墨浆高白度漂白初步研究

通过对脱墨浆(主要是旧新闻纸脱墨浆)漂白的研究,探求获取高白度漂白脱墨浆的途径.结果表明,采用螯合剂预处理的H2O2-FAS两段漂白效果优良,白度增值达到11.9%ISO,浆料最终白度可达66.6%ISO.     

封闭水循环的发展前景

近年来，新纸机的设计车速成倍增加。随着对纸产品质量要求的提高和对二次纤维利用的增加，对过程中水的质量要求也就更高。     

基于层次分析法的智能电表器件选型

智能电表是智能电网的终端,它除了具备传统电表基本的计量功能之外,为了适应新能源与智能电网的使用,还具备通信功能、故障预测、相位检测等智能化功能。但是,关于智能电表的基本核心器件的选型,目前还没有统一的标准,基于此,本文提出一种基于层次分析法的对智能电表元器件选型方案,该方案依据智能电网的发展需求和业务特征,具体分析了智能电网对智能电表的功能需求,并分别针对智能电表具体功能模块的需求特性设置准则层,从而选择出该智能电表所需最优的元器件,为智能电表元器件选型提供科学化依据,支撑智能电网的发展。     

Study on properties of radiata pine wood treated with furfuryl alcohol as fretboard materials for string instruments

European Journal of Wood and Wood Products - The commercial applications of endangered wood species (e.g., ebony, Indian rosewood, and African blackwood) for string instrument fretboards have been...     

Bacterial Community of Koumiss from Mongolia Investigated by Culture and Culture-Independent Methods

The bacterial community of fermented horse milk (koumiss) from Mongolia was studied using three methods: cultivation, direct identification by 16S rRNA clone library and denaturing gradient gel electrophoresis (DGGE). Ninety-eight strains were isolated by traditional cultivation and 61 of those were randomly selected for further identification by 16S rRNA gene sequencing. The strains were dominated by lactic acid bacteria (LAB; six different lactobacilli), Acinetobacter, Bacillus and Psychrobacter. Construction of the clone library analysis revealed that 16S sequences of 220 clones, genus Lactobacillus was dominant, but Streptococcus thermophilus, Acetobacter pasteurianus and uncultured clones were also detected. Ten unique bands were sequenced from the DGGE and revealed: Lactococcus lactis, Lactococcus lactis subsp. lactis, Clostridium acidurici, Acinetobacter johnsonii, Dickeya sp., Enterobacter sp., Pseudomonas sp., Raoultella sp., and Ruminococcus sp.. In vitro growth inhibition of three human pathogens, Escherichia coli, Enterobacter sakazakii and Staphylococcus aureus by 14 culturable bacteria displayed that only three of the isolates tested inhibit growth of E. sakazakii while most of the other bacteria delayed growth of the target bacteria.