Seep/w在坝基墙幕结合防渗体系结构优化中的应用

在墙幕结合的防渗体系中,上部防渗墙和下部帷幕灌浆的结构尺寸大多是凭经验取得的.文章主要从工程防渗效果及安全性、经济性等方面出发,应用渗流有限元数值模拟软件Seep/w,采用图解最大梯度法,对墙接幕防渗体系的结构尺寸进行优化,得出既能满足防渗要求,又能确保工程安全、经济的最优化深度.     

起爆方式对智能雷战斗部毁伤概率的影响

为了提高智能雷对坦克目标的毁伤概率,在应用LS-DYNA有限元软件模拟智能雷多爆炸成型弹丸MEFP(multiple explosively formed penetrator)战斗部形成过程的基础上,分析了采用中心点起爆和多点起爆方式MEFP战斗部在爆轰载荷作用下的成型规律,建立了2种起爆方式下智能雷战斗部毁伤数学模型,编制了智能雷战斗部攻击坦克顶甲的仿真程序,仿真得出了2种起爆方式下智能雷战斗部的毁伤概率。结果表明:起爆方式对智能雷毁伤概率的影响与MEFP战斗部子装药设计有关。进行智能雷战斗部设计时,需要针对不同距离目标选择设计战斗部子装药的个数,并采用相对应的起爆方式,才能有效地提高智能雷毁伤概率。     

多层板架结构在2次攻击下的动态响应分析

为研究多次爆炸作用下舰船舷侧多层防护结构的破坏变形情况,借助于大型有限元分析软件AN-SYS/LS-DYNA对该结构在2发武器攻击下的动态响应进行模拟,分别分析了炸药相对加强筋位置不同的3种模型,在武器同时攻击和先后攻击下的破坏情况,描述了钢板的破口大小、最大位移、有效应力以及塑性区的范围等动态参数。对2种攻击情况进行了分析比较,结果表明,破损结构在遭受第2发武器攻击时产生的破坏更大,因此,2发武器先后攻击更为理想。     

利用二氧化硅地球化学温标计算贵州省温泉深部热储层温度

确定热水系统中最高温度即热储层温度,在温泉开发利用的评价中具有重要意义,通过SiO_2地球化学温标,计算出贵州温泉热储层温度在46°～106℃之间,其埋深在1700～3800m,热储层分布及埋深与大地构造部位密切相关。     

湿陷性黄土地基处理

湿陷性黄土的湿陷变形是影响地基稳定性的一个重要因素.从湿陷性黄土的工程地质特点入手,介绍了湿陷性黄土的两种分类及其各自特点和对建筑物稳定性的影响;分析了对湿陷性黄土地基处理不当在工程中容易出现的"弹簧土"现象,并对"弹簧土"现象的产生做了力学分析;阐述了湿陷性黄土地基处理的原理和方法;以实际工业废水处理工程总结了处理此类问题的经验.可供工程技术人员设计、施工时参考.     

TRAF4 functions as an intermediate of GITR-induced NF-κB activation

Members of the tumor necrosis factor receptor (TNFR) family regulate the activation, differentiation, and function of many cell types, including cells of the immune system. TNFR-associated factors (TRAFs) function as adapter molecules controlling signaling pathways triggered by TNFR family members, such as activation of nuclear factor B (NF-B). Despite intensive research, the function of TRAF4 in signaling pathways triggered by TNFR-related proteins remains enigmatic. Intriguingly, our functional studies indicated that TRAF4 augments NF-B activation triggered by glucocorticoid-induced TNFR (GITR), a receptor expressed on T cells, B cells, and macrophages. Further analyses revealed that TRAF4-mediated NF-B activation downstream of GITR depends on a previously mapped TRAF-binding site in the cytoplasmic domain of the receptor and is inhibited by the cytoplasmic protein A20. GITR is thought to inhibit the suppressive function of regulatory T cells (T_reg cells) and to promote activation of T cells. Taken together, our studies provide the first indications that TRAF4 elaborates GITR signaling and suggest that TRAF4 can modulate the suppressive functions of T_reg cells.Received 20 September 2004; received after revision 8 October 2004; accepted 18 October 2004     

广东坡地不同施钾处理春玉米吸钾特征及产量反应研究

针对广东旱坡地土壤钾素水平低、供钾潜力差这一问题,进行旱坡地春玉米钾吸收特征以及高产施肥技术研究。研究表明,玉米植株不同部位对钾的吸收量,以茎秆最大,占植株吸钾总量的55%以上,籽粒次之,占吸钾总量的18 51%～24 81%;苗期吸钾量比较少,不超过吸钾总量的1%,孕穗期吸钾量不超过吸钾总量的35%,吸钾量最多则在生长的中后期。当施钾肥量水平较底时,增施钾肥,可以显著提高玉米吸收N、P2O5的量;当施钾肥量水平中等时,增施钾肥,亦可以提高玉米吸收N、P2O5的量,但增幅趋缓;当施钾肥量水平较高时,增施钾肥,则会显著减少玉米吸收N、P2O5的量。利用钾素肥料效应方程式和试验结果,对春玉米产量与钾肥施用量进行了统计分析,确定了最高施钾肥量,并总结了玉米高产施钾肥技术。表3,参4。     

密肥因素对春小麦绿叶生长,衰老参数的影响

采用二因素二次饱和Ｄ－最优设计方法，通过建立和解析模型，系统研究了晋２１４８小麦品种叶片生存期，功能期，叶片面积大小及衰老参数与密肥条件的关系；并利用产量和叶面积参数模型，计算求出了当地小麦获得６０００ｋｇ／ｈｍ＾２籽粒产量和３７５０元／ｈｍ＾２毛收益时，生育前期和后期应达到的适宜叶面积值，叶片衰老参数值及有利于增大叶片面积，延长叶片生存期和功能期的适宜播种量和施肥量。     

C_PCP与_w_w_CPCP的关系

本文证明了下面２个结果：（１）当Ｘ＊具有ＰＣＰ时，Ｃ＊ＰＣＰ与（ｗ＊－ｗ）ＣＰＣＰ等价；（２）Ｘ＊具有Ｃ＊ＰＣＰ当且仅当Ｘ＊具有（ｗ＊－ｗ）ＣＰＣＰ且对Ｘ＊的每个非空ｗ＊－紧凸子集Ｋ，（ｗ＊－ｗ）ＰＣ（Ｋ）含有Ｋ的一个ｗ＊－稠密Ｇ子集．     

Green tea epigallocatechin-3-gallate is an inhibitor of mammalian histidine decarboxylase

(–)-Epigallocatechin-3-gallate, an antiproliferative and antiangiogenic component of green tea, has been reported to inhibit dopa decarboxylase. In this report, we show that this compound also inhibits histidine decarboxylase, the enzymic activity responsible for histamine biosynthesis. This inhibition was proved by a double approach, activity measurements and UV-Vis spectra of enzyme-bound pyridoxal-5-phosphate. At 0.1mM (–)-epigallocatechin-3-gallate, histidine decarboxylase activity was inhibited by more than 60% and the typical spectrum of the internal aldimine form shifted to a stable major maximum at 345nm, suggesting that the compound causes a stable change in the structure of the holoenzyme. Since histamine release is one of the primary events in many inflammatory responses, a new potential application of (–)-epigallocatechin-3-gallate in prevention or treatment of inflammatory processes is suggested by these data.Received 8 April 2003; received after revision 20 May 2003; accepted 3 June 2003