Analysis on AE characteristic and its confining pressure effect of outburst coal containing gas

Briquette samples made of outburst coal are taken as study objects to study AE characteristic and its confining pressure effect by using self-developed equipment, Shimazu servo test machine and AE monitor system, and the characteristic of AE parameters are analyzed, too. The results show that in the process of outburst coal containing gas triaxial compression, there is no serious dense or sparse area of AE events, but three relative dense appear in compression phase, middle area of linear elastic stage and near peaking phase area so that the characteristic of AE events look like three peaks. But the amplitude of AE events is small and the good consistency between energy change and amplitude change is showed. Microstructure change caused by external stress field change, fracture and fragmentation of particle of samples, movement besides particle of samples and microstructure change caused by dissipation of gas are the sources of AE events. The number of AE events is reduced as the confining pressure is increased, but the influence on total number of AE events caused by confining pressure show nonlinear, expressed by quadratic function. The number of larger amplitude of AE events show decreasing tendency as the confining pressure is increased, the relation between numbers of AE events whose amplitude is more than certain value and confining pressure is expressed by quadratic function.     

人造板甲醛释放量不同检测方法之间的相关性分析

甲醛释放量是评价木制品对环境和人体健康是否有危害的重要指标,针对当前我国、美国、欧盟、日本等国内外广泛使用的甲醛释放量测定方法,通过进行对比和分析建立数学相关性方程,为生产企业提高检测效率和降低检测成本,保障出口木制品的质量提供参考。     

抚育间伐对人工林影响的研究进展

抚育间伐对人工林有重要影响。针对抚育间伐对人工林的林下植被多样性、生物量、凋落物分解、土壤肥力和森林生态系统碳储量影响的研究进行综述,并提出今后的研究重点应该放在抚育间伐后人工林的生物多样性和生物量的长期定位研究,抚育间伐调控人工林凋落物分解的机制和对人工林生态系统碳储量影响的研究等方面,并需要开展各地区主要森林类型、多种立地条件和不同密度森林的抚育间伐研究。     

气相色谱法检测湖南掺杂油茶籽油

采用气相色谱法,对自行提取的16个湖南油茶籽样品、湖南本地的20家油茶籽油生产企业生产的油茶籽油进行脂肪酸组成测定,并对不同比例的大豆油、花生油、玉米油、葵花油、菜籽油、米糠油、棕榈油和油茶籽油组成的二元体系的样品进行了脂肪酸组成分析。通过分析脂肪酸组成的变化,建立了应用气相色谱法快速、精准地检测油茶籽油中掺杂大豆油、花生油、玉米油、葵花油、菜籽油、米糠油、棕榈油含量的油茶籽油掺假判定方法。     

均质压力对豆乳贮存过程中物性变化的影响

以豆乳为原料,通过不同均质压力处理后,将样品存放在常温(25℃)环境下,持续观测30 d,研究不同均质压力下贮存过程中豆乳的黏度、色差、丙二醛含量和蛋白稳定性的变化。发现在15～40 MPa的均质压力下,豆乳黏度无明显差别;贮存过程中,色差△E值在第20天时为8.51,感官评价消费者中不可接受,黏度和稳定性有极大差异。     

黄连不同提取物对柑橘采后贮藏效果的影响

通过对黄连进行醇提取和水提取,以蒸馏水浸泡为空白对照组对比化学保鲜剂咪鲜胺,研究其不同提取物处理后柑橘生理生化及营养成分的变化规律（贮藏温度10℃,相对湿度85％~90％）。结果表明,黄连提取物较空白对照明显延缓了柑橘果实的腐烂,降低了果实的呼吸强度,抑制贮藏后期果实可溶性固形物、酸及VC含量的下降和丙二醛含量的积累,降低其PG和POD活性,其中黄连醇提取物的处理效果优于水提取物,且与咪鲜胺处理无显著差异。     

指纹图谱技术在茶叶研究上的应用

茶叶品质难辨易形成混乱的市场局面,制约了茶产业现代化发展进程。近年来,指纹图谱技术在茶叶感官品评、质量控制和产地判别等方面的应用越来越多,为茶叶的品质鉴定提供了有效的技术支撑。文章就茶叶指纹图谱技术方法进行了综述,包括气相色谱(GC)、高效液相色谱(HPLC)、毛细管电泳(CE)、红外(IR)及近红外光谱(NIR)、核磁共振(NMR)等,并对指纹图谱技术在茶叶应用上存在的问题进行了分析,对其今后的发展做出了展望,为指纹图谱技术在茶叶上的进一步应用提供理论基础和参考依据。     

超级稻宁粳1号与常规粳稻CH4排放特征的比较分析

以超级稻宁粳1号和常规稻镇稻11为材料,采用盆栽试验,系统比较了两个品种的生产力及CH4排放的差异,并分析了其主要原因。结果表明,虽然两个品种的CH4排放通量的动态特征和生物学产量均基本相似,但宁粳1号的CH4排放总量比镇稻11低35.22%(P<0.05),土壤水溶液中CH4平均浓度也低41.31%(P<0.01)。两个品种的CH4排放差异主要出现在水稻生长中期,前期和后期的差异不明显。比较两个品种的生物学产量、株高、叶面积、根系等生长特性,发现宁粳1号强大的根系是降低CH4排放的最关键因素。综合比较植株生产力和CH4排放强度,发现宁粳1号不仅具有更高产量,而且单位干物质和籽粒产量的CH4排放量均分别比镇稻11低42.42%和81.38%(P<0.05)。上述结果显示,水稻产量的提高不一定伴随CH4排放的增加,选育高产低排放的水稻品种是可能的。大面积推广应用超级稻,可能不仅利于粮食安全,也有利于温室气体减排。     

Variation in mammal species richness and relative abundance in the Karoo§

Understanding how climate change and land transformation may impact the distribution and diversity of wildlife species requires landscape-level foundational biodiversity surveys. The Karoo BioGaps Project aims to provide such data and to support the scientific assessment for shale gas development projects in the Karoo basin. In this paper we present the findings of the BioGaps mammal survey, which recorded medium and large mammals across twenty-five 1 km × 1 km sampling sites within the proposed fracking footprint using camera trapping techniques. We use sample rarefaction curves, non-parametric species richness estimators and non-metric multidimensional scaling plots to explore both species richness and community structure. We also used a generalised linear model to investigate how species diversity varies with both site-specific and landscape-level predictors. A total of 38 species were recorded at the majority of sites. Longitude (z = 4.018, p = 0.0005) emerged as the best predictor of species diversity across the study area, which we suggest is linked to the clear east–west aridity gradient. Together these results reveal the cosmopolitan distribution of the mammal taxa in the Karoo and could be used to inform decision-making linked to mining activities in the area.     

Physiologic and biochemical measurements and response to noxious stimulation at various concentrations of MS‐222 in Koi (Cyprinus carpio)

ObjectiveTo evaluate the physiological effect and response to noxious stimulation at five concentrations of MS-222 in koi (Cyprinus carpio).Study designProspective experimental study.AnimalsTwenty-one healthy adult unknown sex koi fish weighing mean 450 ± SD 120 g.MethodsEach fish was exposed to five different concentrations of MS-222 (50, 70, 110, 150 and 190 mg L^?1) in a random sequence during the same anaesthetic event. For each concentration of MS-222, vital functions such as heart rate (HR) (via Doppler) and opercular rate (OpR) were recorded after a standardized induction period. Response to two noxious stimuli in the form of haemostat clamp pressure applied on the tail and the lip was evaluated, and blood was drawn to measure biochemical and blood gas values.ResultsDecrease in response to noxious stimulation with an increase of MS-222 concentration both for the lip (p = 0.0027) and the tail (p < 0.0001) stimulus was observed. Biochemical values were unaffected by the concentration of MS-222 with the exception of lactate concentration which was weakly correlated with the duration of anaesthesia (r = 0.31, p < 0.001) and the number of times the fish was clamped or bled prior to sampling (r = 0.23, p < 0.001). Opercular rate decreased with the increase in anaesthetic concentration, and HR was not affected.Conclusions and clinical relevanceOur results indicated a decrease in response to stimulus and a decrease in OpR that were associated with increased concentrations of MS-222. This may assist in establishing anaesthetic protocols using MS-222 in fish and supports the use of supramaximal pressure stimuli to teleost fish under variable MS-222 concentrations as a model for future studies.