查询词典 stress

The biomass of rice were not affected by partial-root water stress under those three nitrogen forms, but root parameters of sole nitrate supply decreased significantly under water stress compared to non-water stress part. Water stress stimulated the absorption of NO_3~--N. The photosynthesis rate was inhibited by water stress under NO_3~--N supply, but no effects under NH_4~+-N supply.

局部根系水分胁迫对3种供氮形态营养水稻总生物量没有明显影响，但对单供NO_3~--N营养水稻根系的生物量、根系总长、根体积、平均直径以及根表面积的影响最大，均以未受水分胁迫的一侧根系生物量明显高于另一侧。

The results showed the maximum cyclic stress of CFRP bar should be under 70 percent of ultimate tensile stress; when the maximum cyclic stress decrease 5 percent of ultimate tensile stress, the fatigue life of CFRP bars increase generally 10 times; with the decrease of cyclic ratios, the fatigue life of CFRP bars decrease heavily; for the brittleness, CFRP bar should possess a higher reserve of strength, the margin of safety against failure is a necessity; according to experimental cyclic stress-fatigue life curve, the fatigue behavior of CFRP bar is much better than the fatigue behavior of Q235 steel.

将纤维复合材料用于土木工程结构的研究成果，已应用于实际工程【2j_国外对CFRP筋的一些短期性能以及CFRP筋构件的粘结性能、CFRP加筋混凝土结构的抗弯性能等都做了大量的研究，但对其长国家自然科学基金50278029，50538020和交通部西部交通科技200l431882021资助项目。2OO6年2月13日收到初稿；2006年9月4日收到修改稿。本文联系人：欧进萍，院士期性能如疲劳性能的研究还不够

Indoor flexural fatigue tests are carried out, the results are analyzed and two types of double logarithm fatigue equation under different stress level andequivalent stress level are got. Using the fatigue equation, the fatigue performance of porous concrete and common semi-rigid base materials and cement concrete are compared, the fatigue stress coefficient which is used in the load stress calculation for porous concrete as undersurface of cement concrete pavement and the tensile strength structure coefficient which is used in the flexural stress check for porous concrete as base of asphalt pavement are obtained.

进行室内小梁弯拉疲劳试验，对疲劳试验数据进行分析，得出多孔混凝土不同失效概率下两种形式的双对数疲劳方程，利用疲劳方程，将其疲劳性能与常用半刚性基层材料和水泥混凝土进行比较，还得出了多孔混凝土作为水泥混凝土路面下面层荷载应力计算的疲劳应力系数，和作为沥青路面基层层底弯拉应力验算的抗拉强度结构系数。

An unit initial stress method to calculate stress intensity factor is introduced, which uses the degradation of the 1/4 node singular unit, calculates the stress through the crack tip close to the best stress point, and gets the stress intensity factor.

提出一种计算应力强度因子的单元初始应力法，该法采用退化的1/4节点奇异单元，通过近裂尖最佳应力点应力进行求解，进而求得应力强度因子。

Water stress is one of the most important abiological stress to maize seedling .In this study, we arm to identify the sensitive stage of maize seedling to water stress and select the material which tolerance to flooding. And we use waterlogging tolerance index to identify the sensitive stage of maize seedling. we have studied 20 inbred lines of maize which seedlings under water stress in three stage. The result show that the three leave stage is the most obvious stage to flood stress. In addition, we have analyzed ten of the inbred lines to re-act the waterlogging tolerance index. The result show good re-action. And the result also show that waterlogging tolerance index is a credible index to select waterlogging tolerance materials in seedling.

涝渍是玉米苗期主要的非生物逆境胁迫之一；本试验通过对20份玉米自交系进行苗期的淹水对照试验，采用了三个处理时期，并利用耐渍系数作为指标进行敏感时期的鉴定，结果表明三叶一心期是淹水的相对最佳时期；同时利用其中10份自交系对耐渍系数的重演性进行了分析，结果表明其重演性很好；同时结果还表明耐渍系数是耐渍性鉴定的一个可靠指标。

Abstract］ objective to explore the occupational stress status in head nurse.methods sixty one head nurses completed the osi-r.results there was occupational stress in head nurse.there was significant difference of occupational stress among head nurse with different age,educational background,job title,time to hold a post.conclusion head nurse is matrical leader,who plays important role.each medical treatment organization should be as far as possible to reduce occupational stress and relieve the occupational stress,in order to protect their spirit and body health.

职业紧张或称职业应激、工作紧张，一般是指在某种职业条件下，客观需求与主观反应之间失衡而出现的生理变化和心理压力，以及由于不能满足需求而引起相应的功能性紊乱［1］。21世纪，临床护理工作面临着新的挑战和更大的压力。护士长作为医院管理中最基层的领导者和组织者之一，扮演着重要的角色，护理管理水平的高低直接影响到医院管理质量的优劣和医疗水平。因此，了解护士长职业紧张现状，积极提出预防对策，以提高护理管理水平。

This conclusion is based on three groups of experiments with detached root tips of wheat seedlings: By following the time course changes of NO synthase , superoxide synthase and ABA accumulation under dehydration stress, we found that ABA accumulation was preceeded by the changes of NOS and superoxide synthase. ABA accumulation induced by dehydtrion stress and osmotic stress can be blocked by NO scanvegers and NOS inhibitors, while only dehydration stress-induced ABA accumulation can be blocked by ROS scanvegers. Exogenous applied NO or ROS induced ABA accumulation in root tips of wheat seedlings, and synergistic effects were found between NO and NO. The in planta expereiments also proved that ROS and NO are involved in water stress-induced ABA accumulation.Ⅱ.

证据主要来自以离体根尖为材料的实验：(1)通过检测干旱胁迫下小麦根尖NOS活性、O〓合成酶活性和ABA积累的时间变化进程，发现ABA积累滞后于ROS和NO的变化；(2)抑制剂实验表明，NO清除剂和NOS抑制剂可以抑制自然干旱胁迫及渗透胁迫诱导的小麦根尖ABA积累，ROS清除剂抑制自然干旱胁迫诱导的ABA积累而不抑制渗透胁迫诱导的小麦根尖ABA积累；(3)在非胁迫条件下施加外源的ROS或NO可以诱导小麦根尖积累ABA，ROS和NO之间具有协同作用。

According to the stress-strain curve equation of concrete compression, we simplified the rectangle stress graph of the stress on the area of its bending cross-section in this paper. A general formula for the height of equivalent compression stress block and the stress strength formula were deducted.

根据混凝土受压应力－应变关系的常用曲线方程，对受弯截面压区混凝土应力进行了矩形应力简化，推导得到了等效矩形应力图形高度及应力强度的一般公式。

According to the stress characteristics of coal floor with faults, corresponding simplified mechanical model is built to obtain the equations of shear stress and normal stress on the fault, as well as the influential rules of fault dip on shear stress, normal stress and fault activation.

针对含断层缺陷底板的受力特征，建立相应的简化力学模型，分析得到断层面上的剪切应力和法向应力表达式，并研究断层倾角对断层面上剪切应力、法向应力及断层活化的影响规律。

Thus, the stress behaviour of orthotropic steel bridge decks under elastic phase is well understood, in cluding the stress component of each structural system; the membrane and bending stress distribution in ribs, crossbeams and deck plates; the stress concentrations at the edges of cut-outs in crossbeams; the influence lines of stresses at some positions; and the number of stress cycles produced by the passage of a vehicle.

由此，充分完整地了解了正交异性钢桥面板弹性阶段的应力特性，包括钢桥面板各结构体系的应力成分，纵肋、横梁和盖板的薄膜应力和弯曲应力分布，横梁开孔边缘的应力集中，一些部位的应力影响线以及车辆通过引起的应力循环次数等。

It is also known as one of the most poisonous naturally occurring substances.

它也被称为一个最自然发生的有毒物质。

The greatest stress is found at the location on the cross section where V is the largest.

最大应力出现在横截面上V为最大的地方。