Performance analysis of transcritical organic rankine cycle

The performance analysis of a transcritical organic Rankine cycle system driven by exhaust heat is presented by using 24 organic working fluids. Four parameters, such as the net power output, thermal efficiency, exergy efficiency, and mass flow rate of working fluid, are used to evaluate the performance of this recovery cycle. The results reveal that the maximum net power can be obtained for the saturated ORC, when T1/TC is about 0.98～0.99,and the working fluid with higher critical temperature has more net power output. For the supercritical ORC, the higher expander inlet temperature will benefit the net power output, thermal efficiency, and exergy efficiency, as long as the expander inlet pressure isnnot too low. However, the influences of expander inlet pressure on these performance parameters are linked with the expander inlet temperature and working fluids. The capability of doing power output of supercritical ORC is not always better than that of subcritical ORC. Parameters, such as net power, thermal efficiency, and exergy efficiency, and mass flow rate are discontinuous in the process from subcritical conditions to supercritical conditions.     

Sodium nitrite reduces lipopolysaccharide-induced acute lung injury in mice

AIM: To investigate the effect of sodium nitrite (SN) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and its underlying mechanism in mice. METHODS: All male Institute of Cancer Research (ICR) mice were randomly divided into five groups: Control group; LPS group; and SN 4.8 nmol/L, SN 48 nmol/L, SN 480 nmol/L (ip) groups. Lung wet weight/dry weight (W/D) ratio and permeability were detected. Neutrophil infiltration in bronchoalveolar lavage fluid (BALF) was measured by cel1 counting and morphological changes in lung tissues were assayed by hematoxylin-eosin staining. The 1evels of interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α) in lung were detected. Nitric oxide (NO) level and nitric oxide synthase (NOS) activity in lung were measured according to the specification. RESULTS: Compared to lung in LPS-induced ALI mice, at doses of 4.8 nmol/L and 48 nmol/L, not 480 nmol/L, SN markedly decreased the lung W/D ratio, total leukocyte number and neutrophil percentage in the BALF, lung permeability, and TNF-α/IL-10 ratio, in lung. SN at dose of 480 nmol/L markedly increased the lung NO level compared to control group. In addition, SN decreased the total NOS and inducible NOS (iNOS) activities compared to LPS-induced ALI mice. CONCLUSION: These results indicate that the protective effect of SN against LPS-induced ALI in mice is associated with the low dose SN-induced NO, as well as the subsequent decrease in iNOS activity and TNF-α/IL-10 ratio.     

近50 a中国降水变化的准周期性特征及未来的变化趋势

通过分区分析了1961-2006年近50 a中国降水周期分量的年际变化特征,并对未来20 a（2006-2026年）降水的可能变化趋势做了预测。结果表明：就年际变化而言,大部分气候区的降水年际变化存在着显著的周期变化,并以高频（准3～4 a）变化为主,且具有相对的稳定性。过去的50 a,各气候区的降水呈现出下降趋势。周期叠加外推的结果表明,未来20 a,除西部干旱（半干旱）区的降水会出现少许的增多外,其余各气候区的降水量会出现弱的减少趋势。     

新西兰防潮型中密度纤维板及其应用

介绍了新西兰生产的高防潮中密度纤维板的性能，特点，产品的一般使用技术要点，以及在家具及室内装修方面的应用技术。     

农两优3135作菜后稻种植表现及高产栽培技术

2012年、2013年农两优3135连续两年参加福建省中稻区试,两年平均产量比对照品种II优明86增产10%左右;2014年、2015年引进在建瓯市水源乡大源村作菜后稻种植,表现高产、抗病。高产栽培技术要点包括适时稀播早播、合理密植、肥水管理、病虫害防治等内容。     

水稻对水稻土中甲磺隆结合残留的响应

Metsulfuron-methyl is one of the widely used sulfonylurea herbicides. However, approximately half of the applied metsulfuron-methyl may remain as bound residues in soil. To characterize the response of rice plants to residual metsulfuron-methyl in soil, the activities of acetolactate synthase （ALS）, superoxide dismutase （SOD）, peroxidase （POD）, and catalase （CAT） were investigated in two rice varieties that differed in susceptibility to the herbicide. Changes in the activity of these enzymes in leaves and roots of Xiushui 63, a sensitive rice variety, were greater than those in a resistant variety Zhenong 952. Irrespective of variety, changes in the enzyme activity were greater in the roots than in the leaves. The activities of ALS and CAT decreased, while the SOD activity increased with the increase in the amounts of bound residues of metsulfuron-methyl （BRM） in soil. The POD activity increased at the BRM level of 0.025 mg kg^-1, but decreased at the BRM level of 0.05 mg kg^-1. The results showed that the bound residues of sulfonylurea herbicides may affect metabolism of rice plants.     

日粮磷和钙磷比例对小型猪(香猪)血清、肠、骨碱性磷酸酶及血清钙磷的影响

36头生长阶段香猪去势公猪 ,通过3×3析因安排分组 ,完全随机区组设计 ,随机分配到9个处理中 ,每个处理4个重复 ,每个重复1头猪。试验两个因子中日粮磷的3个水平分别为0.3 %、0.6 %和0.9 % ;日粮钙磷比例的3个水平为1 :1、1.25 :1和1.5 :1。试验基础日粮由玉米、豆粕、血粉和苜蓿粉组成 ,各处理日粮磷水平和钙磷比例用CaCO3、Na2HPO4 和CaHPO4 调配。从试验开始到结束 ,每隔两周颈静脉采血一次测血清AKP活性和钙、磷 ,并于试验结束时屠宰全部试验猪取小肠和肋骨样测AKP活性。试验结果表明 ,血清AKP活性和第六肋骨AKP活性随日粮磷从0.3 %增加至0.9 %显著下降(P<0.05) ,但十二指肠AKP活性不受日粮磷水平影响。日粮钙磷比例不影响血清、第六肋骨和十二指肠AKP活性(P>0.05)。血清磷随日粮磷增加而增加 ,随日粮钙磷比例增加而下降。血清钙不受日粮磷水平影响 ,但在日粮钙磷比例为1.25 :1时最高     

天敌气味对啮齿动物行为的影响

许多啮齿动物都对天敌的气味有回避反应。啮齿类动物的反捕食防御包括对捕食者产生的化学信息的反应和对捕食者气味的回避。本文在文献阅读的基础上, 针对天敌的气味(如皮毛、尿液、粪便以及肛腺分泌物)对啮齿动物的行为影响进行了综述, 其中包括天敌气味对其活动的抑制作用, 对非防御性行为的影响和对栖息地选择的影响等。     

Proliferation and apoptosis of neuroendocrine cells in ovarian epithelial tumors

AIM: The purpose of this study was to observe the morphological features of neuroendocrine cells (NECs)， their proliferation and apoptosis in ovarian epithelial tumors, and to discuss their biological and clinical significance. METHODS: 79 specimens of ovarian epithelial tumor samples were collected, of them 20 benign, 18 boderline, 41 milignant tumors, and 22 normal ovaries were investigated immunohistochemically. Chromogranin A was used to detect NECs and their proliferation and apoptosis were examined by double-label staining of chromogranin A and Ki67 or TUNEL. RESULTS: The positive rate of CgA, distribution and staining intensity in ovarian epithelial tumors were higher than those in normal ovary. NECs showed various shapes with neuronoid protuberances stretching to the neighboring cells or basement membrane. Occasionally, they might touch together. No TUNEL positive coexpression in all NECs was observed by double-label staining, but some NECs were coexpressed with Ki67. CONCLUSION: NECs of ovarian epithelial tumors like cancer cells showed a proliferation, but no apoptosis. Their secretion might promote their neighboring non-NECs to proliferate and prevent them from apoptosis.     

荒漠草原自然恢复中植物群落组成及物种多样性

摘要：通过调查封育3、4、5、6、7年及未封育荒漠草原群落的特征,研究了不同封育年限下草原植物群落组成及生物多样性的变化,以期探明封育对荒漠草原群落恢复的影响。结果表明,封育改变了草原植物群落组分,表现为随封育年限延长,多年生草本植物,特别是短花针茅(Stipa breviliora)等一些地带性物种比例增加;封育草原的Shannon Wiener指数、Pielou指数、Simpson指数均比未封育草地高,封育5年草原的多样性指数最大。