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1.
新仪器能在线、连续、精确地测量浆液密度、体积流量、质量流量和累积流量 ,其测量范围和精度分别为 0 .3~ 3.0 g/cm3、0 .3% ,0 .0~ 4 .0 m3/min、0 .3% ,0 .0~ 4 0 0 0 kg/min、0 .3% ,0 .0 0 m3~无穷大 .在新仪器的基础上 ,提出了质量守恒法、密度法和体积法三种判断溢流和井漏的方法 ,其判断的准确性和快速性比现用的体积法有很大提高 .  相似文献   

2.
基于长喉径文丘里管的双差压湿气流量测量   总被引:2,自引:0,他引:2  
为实现湿气气液两相流量的在线非分离测量,提出一种基于长喉径单文丘里管的双差压湿气流量测量方法.通过理论分析和实验研究,揭示了湿气液气质量比和气相流速与长喉径文丘里管收缩段差压、扩张段差压之间存在一定的内在变化规律及物理本质.为有效提高测量精度,针对传统虚高模型的缺陷,提出了虚高模型的优化原则.建立了基于单文丘里管的气液两相测量模型,并通过迭代运算实现了气液两相流量的分相测量,对于压力P为0.10—0.16MPa,气相弗劳德数0.4~0.7,液气质量比0~1范围内,气相流量测量的相对误差优于±3%,液相流量测量的满度误差小于±10%.  相似文献   

3.
研究采用人工复配功能菌的生物强化法提高生物膜填料塔烟气同时脱硫脱氮性能,对入口气体SO_2和NO_x的浓度、气体流量、循环液流量等因素对功能菌复配前后生物膜填料塔烟气同时脱硫脱氮效率影响进行实验.结果表明,在入口气体SO_2和NO_x的质量浓度分别为1 500~3 000 mg/m3和1 400~1 600 mg/m3,气体流量为0.2 m3/h,循环液流量为9.0 L/h的最优条件下,功能菌复配后生物塔的脱氮率达到62.03%,比复配前(44.81%)提高了17.22个百分点,而生物塔的脱硫率在复配前后均为100%.  相似文献   

4.
利用液液萃取-高效液相色谱-二极管阵列检测方法建立了牛奶中氯霉素残留的分析方法。牛奶样品加入冰醋酸和饱和氯化钠溶液后用乙酸乙酯萃取,萃取液浓缩并转溶于乙腈中,用正己烷脱脂,最后浓缩定容于流动相中,进行仪器分析。氯霉素浓度在20~1 000 ng/m L范围内线性良好,方法的加标回收率在86.5%~94.4%之间,最低检测限为2ng/m L。  相似文献   

5.
科氏质量流量计测量单相流具有很高的精度,但在气液两相流工况下,科氏流量计测量性能下降,质量流量测量误差急剧增加.为减小测量误差和量化气体体积分数,本文对液相质量流量测量量程0~1 000 kg/h的科氏流量计,结合差压变送器,进行了含气率0~30%的气液两相流实验,并设计了基于粒子群优化算法-支持向量机(PSO-SVM)数据驱动的质量流量修正和含气率预测模型.PSO算法提高了模型构建的速度与预测精度.其中,差压可提供流动形态、相含率等信息,是模型的重要输入变量,包含该变量构建的模型对质量流量修正的相对误差为±1.5%,预测含气率的绝对误差为±3%.由于差压变量需外接差压变送器获取,存在安装不便、空间受限的问题.为实现一体化测量,利用科氏流量计自身动态信号来替代差压变量,并保证模型精度在可接受范围内.结合实验数据分析,设计了另外一种去除差压变量、输入变量完全基于科氏流量计自身信号的两相流测量模型.采用质量流量测量值方差替代差压,修正质量流量,对含气率预测设计了两级SVM模型,将质量流量修正的绝对偏差作为含气率预测模型的输入,以替代差压.结果显示,该模型对质量流量修正后的相对误差为±2%,...  相似文献   

6.
传统液膜厚度测量方法会干扰液膜流动进而引发测量偏差,为了克服传统测量方法的不足,提出了采用超声多普勒进行非介入式测量液膜厚度的新方法,通过超声多普勒流速仪测量气液界面回波信号,通过反射回波识别气液界面测得液膜厚度,通过对液膜速度分布曲线进行积分,还可获得液相质量流量。在气液两相流实验环道上开展了测试,液相折算速度范围为0.027~0.066 m/s,气相折算速度范围4.85~15.81 m/s。实验表明:液膜厚度的分辨率0.01 mm,液膜厚度最大测量误差4.32%,液膜质量流量最大误差5.0%。  相似文献   

7.
取自云南红酒厂的酒精废醪液经固液分离后,在恒温30℃下,滤液分别采用批量发酵工艺和半连续工艺进行了厌氧发酵产沼气的实验.实验结果表明,发酵滞留时间为15d,原料产气率为0.23m3/kgCOD;24d后,批量发酵的产气量与COD降解间的关系为:245L/kgCODremoved,COD降解率为85.24%;半连续发酵的产气量与COD降解间的关系为:285L/kgCODremoved,COD降解率为69.79%.  相似文献   

8.
使用生物膜填料塔净化烟气中的NOx.实验结果表明,循环液pH、循环液流量、NOx气体进口浓度、气体流量对生物膜填料塔的NOx净化效率和生化去除量有显著影响.在NOx进口气体浓度为900mg/m3、气体流量为0.2m3/h、循环液pH为6.0、循环液流量为10L/h的最佳操作条件下,生物膜填料塔可以脱除烟气中80%左右的NOx.生物膜微生物的优势种为少动鞘氨醇单胞菌,通过平板计数法得到的生物膜最大活菌数为1.455×107CFU/g.  相似文献   

9.
给出了一种完全基于CMOS工艺的热风速传感器及其封装的结构、工作原理以及测试结果.该传感器由加热元件和测温元件构成,多晶硅加热电阻元件产生一定的温度分布,CMOS纵向衬底晶体管实现由风速导致的温度变化的测量.传感器的封装采用导热胶在背面贴陶瓷的方式进行.该传感器采用恒温差工作模式,风速测量采用热损失型原理,测试电路是由仪器放大器组成的控制和测试系统.经过风洞测试,风速的测量可以达到30 m/s,风速分辨率达到0.5 m/s.传感器的功耗最大值小于100 mW.  相似文献   

10.
在模拟地层上覆压力、地层压力、地层温度和地层含水饱和度的长岩心上,模拟不同生产压差下的气体流速实验,确定了川西蓬莱镇组气藏的单井合理产量为压裂前922m3/d至3072m3/d,按平均增产5倍计算,蓬莱镇组气藏压裂后的单井合理产量为4600m3/d至15400m3/d,反推的单井无阻流量为18400~118300m3/d,与气藏实际值基本一致.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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