离析对沥青稳定碎石路用性能的影响

为了研究离析对沥青稳定碎石路用性能的影响,采用制作的大马歇尔试件进行了浸水马歇尔试验、混合料车辙试验和构造深度试验,研究了离析对混合料三个方面的影响。研究结果表明:混合料离析造成粗集料集中区域水稳定性变差;混合料离析导致粗集料集中区域性能变差;离析对沥青混合料各方面性能影响有着较大差异。     

多孔沥青混合料路用性能分析

多孔沥青混合料在水稳定性以及抗冻性和疲劳特性等性能方面和传统的密级沥青混合料存在着明显的区别。本文通过对多孔沥青混合料PAC-13的路用性能进行实验研究得出了,采用多孔沥青混合料进行施工,在水和热以及荷载耦合等作用下,路用性能表现出色。但是多孔沥青混合料在低温性能上则相对于密级沥青混合料相对较差。但是抗冻性能良好,而多孔沥青混合料会随着空隙率的增大而降低。     

废旧橡胶粉改性沥青混合料的性能研究

为检验废旧橡胶粉对沥青混合料性能的影响,对废旧橡胶粉沥青拌制的沥青混合料(AC)进行试验研究,并与普通沥青混合料对比,结果表明废旧橡胶粉改性沥青混合料具有优良的高温性能、低温性能和水稳定性均有改善。     

除冰填料对沥青混合料性能影响研究

为了研究除冰填料对沥青混合料路用性能的影响,采用等体积替代法进行沥青混合料配合比设计,并对不同掺量除冰填料对沥青混合料高温稳定性、低温性能以及水稳定性能进行了对比分析。试验结果表明:除冰填料对沥青混合料高温性能与水稳定性具有显著影响,对低温性能也有一定影响;建议将水稳定性与低温性能作为除冰沥青混合料配合比设计关键控制指标,且除冰填料替换掺量不应超过50%。     

纳米TiO_2对沥青路用性能影响研究

将纳米TiO_2掺入沥青混合料以降解汽车尾气近年来已有较多研究,但其是否会影响沥青混合料的路用性能是值得关注的问题。为掌握掺入纳米TiO_2对沥青路面性能的影响,本文对国内外相关研究成果进行了总结。发现掺入纳米TiO_2后对沥青混合料的高低温性能、水稳定性与疲劳性能均有一定程度改善。     

沥青路面再生技术的指导方针和应用

旧沥青混合料再生技术目前已成为国际上道路维修改造的主要方法之一。以就地热再生技术为研究对象,对旧料性能评价、再生沥青混合料配合比设计、生产工艺等关键技术进行了研究。通过室内试验,结合实际工程,表明再生沥青混合料具有良好的路用性能,经济效益和社会效益十分明显。     

浅谈沥青混合料拌合质量控制

沥青混合料的拌和对于沥青混合性能的好坏有着重要影响，高等级公路的沥青混合料拌和对拌和时应注意的事项有着严格的规定。本文主要对沥青混合料拌和质量控制要点以及检测分析方面进行了阐述。     

掺加Sasobit的橡胶沥青与温拌橡胶沥青混合料路用性能研究

为了评价温拌剂对橡胶沥青的降温效果及其对橡胶沥青混合料路用性能的影响,对掺加Sasobit后的橡胶沥青胶结料进行性能测试,结合橡胶沥青混合料正常温度拌和成型的试件,与分别添加Sasobit后降低拌和成型温度制作的橡胶沥青混合料试件进行测试分析,结果表明,Sasobit使橡胶沥青胶结料的高温稳定性得到提高,Sasobit可以使橡胶沥青混合料在较低的拌和成型温度制作试件,孔隙率不变,低温抗裂性、高温稳定性及水稳定性得到提高.因此,通过添加Sasobit降低橡胶沥青混合料的拌和及成型温度是可行的.     

浅谈沥青混合料拌合质量控制

沥青混合料的拌和对于沥青混合性能的好坏有着重要影响,高等级公路的沥青混合料拌和对拌和时应注意的事项有着严格的规定。本文主要对沥青混合料拌和质量控制要点以及检测分析方面进行了阐述。     

基于玄武岩纤维沥青混合料路用性能研究

随着重轴载车辆以及交通量逐年增长,我国公路的使用年限严重缩短。因此,延长道路的使用寿命和改善道路的使用性能是我们现阶段努力的重点。玄武岩纤维与常规纤维相比具有韧性好、密度大、力学性能好、容易与沥青混合料拌合均匀等优点。本文通过对掺入玄武岩纤维的沥青混合料路用性能研究,分析评价玄武岩纤维的掺入对沥青混合料相关性能的改善效果。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.