恒定

Based on Bernoulli equation of unsteady flow, a random walk model is presented firstly for numerical simulation of unsteady flow in river networks.

首次从非恒定流能量方程出发，建立随机游动模型，用蒙特卡罗方法数值模拟大型河网非恒定水流运动。

In a constant electric field, a charged particle experiences constant acceleration.

在恒定电场中，带电粒子得到恒定的加速度。

A numerical calculation program is written up for the various solution methods in this paper and the program is being used in various aspects of inverse problem of environmental hydraulics, including inverse problem in reverse process of one-dimensional unstable diffusion, inverse problem in reverse process of convection-diffusion, inverse problem for the dispersion coefficient in water quality model, The inverse problem of coefficient identification for nonlinear Boussinesq equation, parameter identification inverse problem for water quality model, the inversion of parameter of BOD-DO water model, the inverse problem of the source of convection-diffusion, identification of the steady-state permeability for two dimensional isotropic medium, two-dimensional steady inverse problem of convection-diffusion and parameter identification inverse problem for two-dimensional parabolic equation, etc.

对本文提出的各种算法，编制了数值计算程序，并把它应用于环境水力学反问题诸多领域，包括污染物一维非恒定扩散逆过程反问题，对流扩散方程逆过程反问题，河流水质纵向弥散系数反问题，非线性Boussinesq方程反问题，河流水质多参数识别反问题，BOD-DO水质模型参数反演问题，对流—扩散方程源项反问题及二维恒定各向同性介质渗透系数反问题，二维定常对流——扩散方程及二维抛物型方程参数控制反问题等。

Therefore, if we have a way of holding emitter current constant through a transistor, the transistor will work to regulate collector current at a constant value.

于是，只要我们能让晶体管的发射极电流保持恒定，它就能保持发射极电流为恒定值。

The secondary settling tank in COST 624/682 benchmark wastewater treatment plant under storm weather was used for steady-state and dynamic simulations of settling tank operation under two different control strategies, constant return rate and constant return ratio.

以COST624/682中基准污水厂二沉池为研究对象，利用模型对暴雨天气下恒定回流量和恒定回流比2种措施控制下沉淀池的运行情况进行了稳态和动态模拟。

Cryostat tank / tank temperature / low temperature tank is widely used in petroleum, chemical, electronic instruments, physical, chemical, biological engineering, medicine and health, life science, light and food, materials testing and chemical analysis, research departments, universities, businesses quality control and production departments work for the user to provide a hot and cold controlled temperature constant uniform field source, the test samples or products produced by a constant temperature test or test, but also as a direct heating or cooling and auxiliary heating or cooling of heat or cold source.

低温恒温油槽/恒温油槽/低温油槽广泛用于石油、化工、电子仪表、物理、化工、生物工程、医药卫生、生命科学、轻工食品、物性测试及化学分析等研究部门，高等院校，企业质检及生产部门，为用户工作时提供一个热冷受控，温度均匀恒定的场源，对试验样品或生产的产品进行恒定温度试验或测试，也可作为直接加热或制冷和辅助加热或制冷的热源或冷源。

The properties of a detonator were studied by accelerated life test at the conditions of temperature 60℃ and 71℃, relative humidity 95%.

在恒定温度、相对湿度（60℃、95%和71℃、95%）的双因素和恒定温度(71℃)的单因素条件下，对某火工品在加速寿命试验后各个不同时间的性能变化情况进行了研究。

Results KoA for urea varied with dialyzer model, but the effect of Qb, Qd. Urea KoA did not change significantly when Qb increased from 300 to 500 ml/min at Qd of 500, 800 and 1000 ml/min.

结果 透析液流量保持恒定时（分别为500，800，1000 ml/min），尿素KoA在血流量从300增加到400，500 ml/min时，KoA并不增加；但在血流量保持恒定时（分别为300，400，500 ml/min），尿素KoA在透析液流量从500增加到800，1000ml/min时，尿素KoA显著增加。

Through the comparison of DFR genes among the 20 species, it is found that the amount of similarity between the Dianthus plumarius and the Dianthus gratia nopolitanus is the highest with 97 points given.

发现的保守区有：4CL基因在5个物种中有5处4个和4个以上连续的恒定的碱基保守序列。F3H基因在7个物种中有10个部位有5个和5个以上连续恒定的碱基序列。

This constant emitter current, multiplied by a constant α ratio, gives a constant collector current through Rload, provided that there is enough battery voltage to keep the transistor in its active mode for any change in Rload's resistance.

这个恒定的发射极电流，乘以恒定的系数α，就得到流过负载Rload的恒定的集电极电流。前提是电池电压足够高，不论Rload如何变化，晶体管都能工作在放大区。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。