文蛤对四种单胞藻的表观消化状况及同化率

水温22℃下,显微观察了文蛤对塔玛亚历山大藻及海水小球藻,等鞭金藻和青岛大扁藻的表观消化状况,以灰化法测定了文蛤对四种单胞藻的同化率。结果表明,低浓度时文蛤对四种藻类的表观消化状况优于高浓度组;文蛤对海水小球藻、等鞭金藻和青岛大扁藻的同化率随着藻类浓度的升高而降低,其同化率变化范围分别为87.9%~67.4%、83.4%~58.7%和67.5%~37.9%。当塔玛亚历山大藻浓度低于5.0×103cell/mL时,文蛤不会产生假粪,该藻能够被文蛤摄食。藻浓度在1.0×103cell/mL到3.0×103cell/mL时,文蛤对该藻的同化率从81.8%降至52.3%,4.0×103cell/mL组的同化率升高至67.6%,藻浓度升高至5.0×103cell/mL时同化率又降至52.4%,塔玛亚历山大藻3.0×103cell/mL浓度组是一个分界点,同化率最低,大于这一浓度时,同化率又呈上升趋势。     

基于数值模拟的栓塞修复过程中AE信号分析

为探讨木质部栓塞修复过程监测到大量AE信号现象的原因,基于Rayleigh-Plesset方程建立描述栓塞修复过程中空化泡的运动方程,并用数值模拟方法得到空化泡运动方程的解,对AE信号进行动力学分析。结果表明:当木质部液水势升高时,空化泡会塌缩为半径较小的气泡。但经过一次塌缩并不会使栓塞修复。在压强升高的情况下,气泡会经多次塌缩直到形成稳定的微小气泡,栓塞才会完全修复。在气泡多次塌缩的过程中,气泡半径减小,但是并不是单调减小而是以减幅振动的方式减小,从而形成振源,成为AE信号的来源之一。     

棉铃虫细胞色素P450家族 CYP6AE14 基因克隆、序列分析及蛋白原核表达

采用同源克隆技术克隆石河子棉区棉铃虫抗性品系的P450家族解棉酚基因 CYP6AE14 。克隆获得的目的基因全长1 581 bp,编码526个氨基酸。序列分析表明,该抗性品系的 CYP6AE14 有1个氨基酸发生突变,即Y25F;其与烟草天蛾的CYP6AE32同源性较高,达60%。利用原核表达载体pET28 a在大肠杆菌中成功表达棉铃虫P450 CYP6AE14 基因,为进一步的基因功能验证奠定基础。     

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.     

Automatic detection of a damaged cutting tool during machining I: method to detect damaged bandsaw teeth during sawing

This paper presents an on-line method for detecting damaged teeth in the bandsaw using acoustic emission (AE) signal energy. The method is based on an analysis of differences in AE energies generated by normal and damaged teeth during sawing. Because of the difference in the amount of sawing, the AE energy was low for sawing by the damaged tooth and high for sawing by the normal tooth immediately after the damaged tooth. The ratio of AE energy for two successive teeth — a normal tooth immediately following a damaged tooth — was much greater than 1, whereas the ratio of AE energy for two successive normal teeth was close to 1. The results demonstrate that the technique using the AE energy ratio for two successive teeth is effective for on-line detection of damaged bandsaw teeth.Part of this paper was presented at the 9th Annual Meeting of the Chugoku Skikoku Branch of the Japan Wood Research Society, Tottori, October 1997     

AE油佐剂灭活疫苗对鸡胚和仔鸡的保护力试验

三批禽脑脊髓炎(AE)油佐剂灭活疫苗免疫开产前种鸡,种鸡免疫2~3个月后所产种蛋对禽脑脊髓炎病毒(AEV)鸡胚易感性试验的受保护率达100%,而同期所产种蛋孵出的仔代雏鸡,在出雏后3周内对AEV VR株攻毒的受保护率亦达100%; 种鸡免疫6~7个月后所产种蛋对AEV VR鸡胚易感性试验的受保护率达75%~80%,而同期所产种蛋孵出的仔代雏鸡,在出雏后3周内对AEVVR株攻毒的受保护率达70%~90%。试验结果表明,AE灭活疫苗AEV鸡胚易感性试验的鸡胚保护率与同期雏鸡对AEV VR肌肉途径攻毒的保护率基本相同。     

动态载荷下基于声发射技术的杨木破坏过程检测

利用声发射检测和力学试验相结合的方法,研究山杨木材在动态载荷下的声发射演变过程;结合木材粘弹性特点,通过声发射参数分析研究在不同受力阶段木材的声发射特点.结果表明:1)声发射信号幅值不连续,是跃迁的;材料断裂前声发射信号的幅值和能量比断裂后小,在断裂点对应声发射信号幅值和能量的局部极大值.2)随时间和载荷的变化,声发射累计撞击数和累计能量增加快慢可以体现杨木在受力条件下的完全弹性、弹性为主的弹塑性共存、塑性为主的弹塑性共存3种状态.3)声发射率和幅值参数可以预测材料纤维开始断裂进入危险期的第一"临界点"和材料大量纤维断裂进入严重危险期的第二"临界点",如果继续加载材料将会破坏断裂.     

禽脑脊髓炎的调查及病毒分离

对陕西省宝鸡、渭南等地的24个鸡群进行了禽脑脊髓炎（AE）的调查,所调查鸡群都有产蛋下降史或产蛋正在下降,下降幅度平均为17.2%。用琼扩试验（AGP）检测所采集的256份血清,AE阳性率平均高达85.6%。有10个鸡群阳性率达100%。跟踪调查2个种鸡群,发现孵出的雏鸡从3日龄开始发病,而且有AE的症状,采发病雏鸡的脑组织,接种6龄鸡胚分离病毒,连传3代,琼扩检测分离毒,呈AE抗原阳性,人工感染1日龄雏鸡复制出与原发病鸡群相同的疾例,表明分离毒是AE病毒。     

“全胚双氟碳法”制备禽脑脊髓炎琼扩抗原的研究

用禽脑脊髓炎病毒（AEV）Van Rockel毒株接种6日龄SPF鸡胚，感染11 d后，分别收集鸡胚、绒毛尿囊膜及尿囊液、鸡胚剔除羽毛、眼球、爪和喙后与绒毛尿囊膜一起，制成匀浆，反复冻融3次，通过2次氟碳（三氯三氟乙烷）从全胚匀浆中萃取制备AE琼扩抗原（AGP－Ag)用进口标准AE AGP试剂进行标化，结果发现：制备的AD AGP－Ag与标准阳性血清之间的清晰、致密的沉淀线，并与标准AE AGP－Ag的沉淀线完全吻合，表明两者的沉淀反应一致，从而了AE AGP－Ag制备新方法－“全胚双氟碳法”其制备AE AGP－Ag有如下特点：①产量高，平均每3个SPF鸡可获得1mL AE AGP－Ag; ②特异，与类症阳性血清无交叉反应；③敏感，AGP试验中毋需重复加样，普通琼脂即可出线；④稳定性好，保存期长；⑤与标准AE AGP－Ag阳性检出符合率均达100％。本研究表明用“全胚双氟碳法”制备的AEAGP－Ag达到了进口标准，AEAGP－Ag质量，可用于SPF鸡AE抗体的监测，且生产成本低，也可用于商品鸡AEV感染的检测。     

机插超级稻在不同施肥水平和不同插植密度下的生育特性及产量表现

了研究华南双季稻区超级稻机械化插秧在不同施肥水平和不同插植密度下的生育特性及产量表现,明确超级稻机械化插秧适宜的施肥水平和插植密度。2012年早、晚季,以常规超级稻‘合美占’为材料进行了(0、120、150、180 kg/hm²) 4个施肥水平和(2.4×105穴/hm²、2.85×105穴/hm²) 2个机械化插秧密度试验,结果表明：在相同施肥水平下,插植密度2.85×105穴/hm²的植株干物质积累、叶面积系数和产量都高于插植密度2.4×105穴/hm²的处理且差异显著;在相同插植密度下,植株干物质积累、叶面积系数、有效穗、产量随着施肥水平的提高而增加的趋势是在中低施肥水平下(120~150 kg/hm²),高肥水平(180 kg/hm²)处理反而下降了,施肥量120 kg/hm²处理氮肥农学利用率最高,SPAD值测定结果没有明显规律性。插植密度2.85×105穴/hm²和施肥量120~150 kg/hm²是广东双季稻区机械化插秧取得高产的适宜栽培方案,说明适当密植和合理施肥是提高产量的有效途径。