聚丙烯纤维三灰稳定砂的路用性能试验研究

本文为了改善三灰(水泥、石灰、粉煤灰)稳定砂基层材料路用性能,在其中掺加了适量的聚丙烯纤维。通过室内试验对比研究了掺加聚丙烯纤维的三灰稳定砂和普通三灰稳定砂不同龄期的路用性能指标。研究结果表明,聚丙烯纤维能够提高三灰稳定砂材料的抗裂能力,并改善其路用性能。     

浅谈粉煤灰对普通混凝土的渗透性的影响

耐久性对于混凝土来讲意味着安全、经济、持久.由耐久性失效带来的灾难是巨大的,损失是严重的.在一定意义上讲,耐久性有时要比强度更为重要.渗透性作为耐久性的一个重要方面,直接影响混凝土的破坏.因此,研究混凝土的渗透性显得尤为重要.文章通过研究不同掺量粉煤灰混凝土的渗透性,得出混凝土渗透性测试结果(用渗透系数表示),并作与粉煤灰掺量的回归分析,从而得出粉煤灰掺量与混凝土渗透性的关系,得出相应结论.     

矿物掺合料对外加剂FDN效果的影响研究

外加剂在混凝土中不仅能较低水灰比,而且能提高混凝土的性能,是现在高性能混凝土不可或缺的第五组分,但其对浆体的流动度损失影响制约了外加剂的使用。本文以往砂浆中掺加矿物掺合料来研究改善外加剂对将体流动度的影响。发现矿物掺合料都能在一定程度上改善浆体的流变性,其中碱性较强的矿物掺合料对改善砂浆浆体流动性的效果较好,另外,四中矿物掺合料对改善流动性的效果由大到小依次是:矿渣磷渣粉煤灰硅灰。     

粉煤灰高性能混凝土的工程应用

本文对粉煤灰高性能混凝土的各项性能作了详细的研究,并针对粉煤灰的掺入量对混凝土各种性能的影响以及粉煤灰混凝土在施工中应注意的一些问题进行了分析和探讨。     

石屑与天然细砂搭配在商品混凝土中的试验研究

本文根据石屑棱角多、0.315mm以下颗粒少、含粉量较大、配制的混凝土流动性差,不利于泵送的特点,设计和研究了石屑和细砂复合配制泵送混凝土的优化方案,以及复合砂混凝土和易性和抗压强度的影响。试验结果表明:在水泥掺量一定且石屑和细砂的比例为1∶1时,混凝土的和易性良好、抗压强度最高,坍落度经时损失小,适用于商品混凝土生产。     

南水北调中线工程辉县段水泥改性膨胀土工程特性的试验研究

本次试验研究采用掺加水泥改性膨胀土的方法 ,依托河南水利建筑工程有限公司承建的南水北调中线工程辉县段进行工艺性试验,采用三种不同水泥掺量的膨胀土进行碾压试验研究。通过碾压试验,结果显示随着水泥掺量的增加,渗透系数、抗压强度并不随着水泥掺量的增加而增加,笔者认为弱膨胀土的水泥掺量在3%~5%范围内较为合理,具体掺量应在施工前通过工艺性碾压试验确定。     

粉煤灰水泥混凝土路面性能研究

近年来,我国加快了对道路的建设,而随着道路建设数量的增加,人们对于路面的性能也有了更高的要求。为了有效的提高混凝土路面的建设质量,就需要在在混凝土中混合如一些粉煤灰,这些粉煤灰的应用不仅使得水泥混凝土路面的性能得到了有效的提高,而且也在一定程度上保障了水泥混凝土路面的施工质量,对于道路的建设和发展具有积极的影响作用。本文就粉煤灰水泥混凝土路面性能进行了简要的研究,仅供参考。     

浅谈影响水泥混凝土强度的因素

一般来说,水泥混凝土的强度要从几个方面去考虑,包括水灰对比、水泥的材质、集料、集灰比一级水泥的养护等几个方面,作为建筑的主要材料,水泥的设计和施工上有一些基本的思路需要去遵循,本文从这个角度出发,重点阐述了混凝土强度的问题,以及在生活中遇到的水泥的问题和解决的措施.     

浅谈高强度混凝质量控制

随着我国建筑领域的不断发展,创新高强混凝土也随之产生。高强度混凝土是一种新型的混凝土,它是用水泥、砂、石原材料外加减水剂或同时外加粉煤灰、矿粉、矿渣、硅粉等混合料,经常规工艺生产而获得高强度的混凝土。高强混凝土具有强度高、节材效果好、材料性能优越等特点。本文对高强度混凝土的原材料选择、配合比设计和施工技术进行了详细的分析,并提出工程质量控制措施。     

改善水泥与混凝土外加剂相容性措施的探讨

本文简述水泥矿物成分,含碱量、掺入量、水泥温度及颗粒形状及掺量对水泥与外加剂适用性的影响,改善水泥与外加剂相容性复掺混合材,控制水泥颗粒分布及形状。     

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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。 …