沼气发酵液对烟草赤星菌的抑制研究

用不同浓度和不同温度的沼液对烟草赤星菌作抑菌实验研究，结果表明，即使是10％的沼液对烟草赤星菌也有明显的抑制效果；经巴氏灭菌、煮沸、灭菌后的沼液对烟草赤星菌也有一定的抑制作用，但抑菌趋势表现为温度越高抑菌效果越差。通过对沼液与特效农药菌核净(纹枯利)的比较发现，沼液的抑菌效果，与浓度为1：500的菌核净的抑菌效果相当，且抑制效果更加稳定和持久。     

沼液对某些植物病原菌抑制作用的研究

沼液对大多数植物病原真菌(烟草赤星病菌、稻瘟病菌、甘薯黑斑病菌、三七镰刀菌、香石竹镰刀菌、百合镰刀菌、瓜果腐霉、西芹细菌、石榴病菌)有抑制作用，对病原细菌(三七细菌、魔芋细菌、辣椒疫霉、烟草疫霉、三七丝核菌)抑制效果不太明显。抑菌率随沼液浓度的增加有所增加，抑菌率为50％-80％。经灭菌处理的沼液对病原菌的抑制效果明显减弱，抑菌率不超过20％。     

水葫芦汁中温沼气发酵的实验研究

以鲜水葫芦汁为原料,在30℃恒温下,采用批量发酵工艺,进行发酵产沼气实验,测定发酵产沼气与时间的关系.实验结果表明,鲜水葫芦汁COD的降解率达到86%;鲜水葫芦汁发酵在第10天后达到稳定值,并持续产气25 d;对发酵过程中所产气体进行分析,发现甲烷含量最高能达到60%左右.因此,水葫芦是一种良好的发酵原料.     

大中型沼气工程技术讲座(四)沼气工程的前处理与输配系统

大中型沼气工程工艺流程可分为3个阶段,即预处理阶段、中间阶段和后处理阶段。料液进入消化器之前为原料的预处理阶段,主要是除去原料中的杂物和沙粒,并调解料液的浓度。如果是中温发酵,还需要对料液升温。原料经过预处理使之满足发酵条件要求,减少消化器内的浮渣和沉沙。料液进入消化器进行厌氧发酵,消化掉有机物生产沼气为中间阶段。从消化器排出的消化液要经过沉淀或固液分离,以便对沼渣进行综合利用,这为后处理阶段。由于原料不同,运行工艺不同,每个阶段所需要的构筑物和选用的通用设备也各有不同。1前处理装置选型与设计规模化养猪场粪…     

低温纤维素降解菌系对沼气发酵过程中产酸、产气的影响

将本实验室一组稳定的低温兼性厌氧纤维素降解菌系X1接种到水稻秸秆和牛粪混合沼气发酵底物中,研究其在20℃低温沼气发酵过程中对产酸、产气的影响。结果表明,底物降解时主要产生乙酸、丙酸和丁酸,使pH值下降,处理组处理12 d时乙酸、总挥发性脂肪酸及甲烷含量分别为1.22,2.23 g/L和37.50%,对照组分别为0.47,0.81 g/L和28.50%。处理12 d后随着乙酸含量的逐渐下降,甲烷含量明显提高,15 d为50.20%,24 d达到67.60%,而对照仅为35%和43.30%;总产气量处理较对照提高76.81%。由此可见,菌系X1降解纤维素类物质时为甲烷合成提供了较多的前体物质,有效地提高了甲烷含量和产气量,使产气启动期提前。     

小桐子油枯厌氧消化产气潜力研究

在23±1℃条件下,采取批量发酵工艺,研究了小桐子油枯发酵产沼气的潜力.试验结果表明:小桐子油枯TS,VS产沼气的潜力分别为404.23,435.12 ml/g,原料的TS,VS利用率分别为19.90%,34.30%;通过稀碱溶液调节发酵料液的pH值,有利于厌氧发酵产气的进行,TS,VS产沼气潜力分别升至478.79,515.38 ml/g,原料的TS,VS利用率分别升至25.89%,48.02%.     

醋糟厌氧发酵特性的研究

以醋糟为厌氧发酵原料,分别进行了连续进料试验和全进全出料试验。连续进料试验结果表明,在每天进料量保持不变的情况下,日产气量稳定,平均产气率为0.918 m3/(m3.d),最高产气率可达1.111 m3/(m3.d)。经过计算可知,8.52 kg醋糟可产1 m3沼气。全进全出料发酵试验结果表明,醋糟厌氧发酵的体积上浮和膨胀非常明显。当进料浓度为4%时,料液最大膨胀体积为322.68 cm3,为发酵料液体积的28.8%。醋糟厌氧发酵具有降解速率快,滞留期短等特点。     

木薯酒精废醪产氢潜力的试验以及对产氢产甲烷联合发酵的研究

以木薯酒精废醪为原料,通过调节pH值至5.0,在(35±1)℃的中温条件下进行批量式沼气发酵实验,发酵料液的TS浓度设为6%。实验结果表明,氢气发酵试验的运行时间为11 d,净产气量为1615 mL,产氢潜力为92.13 mL/g(TS)、97.58 mL/g(VS),能源转换效率为1.58%。针对产氢发酵和产甲烷发酵能源转换效率低这一问题,对产氢、产甲烷联合发酵进行了分析,讨论了原料种类、接种量、温度、pH值、发酵浓度、氢气分压等参数对联合厌氧发酵的影响以及对发酵过程中动力学和菌群的探讨,并对以厌氧产氢产甲烷联合发酵的方法处理木薯酒精废醪进行了讨论。研究结果可为以后木薯酒精废醪的能源高效利用提供参考。     

猪场粪水沼气发酵综合处理生产试验

本文介绍了日处理存槽6500～7000头猪场全部粪水的沼气发酵综合利用系统。该系统包括固液分离、制肥、厌氧两步消化和好氧处理4个过程。日处理粪水100～200t/d,产沼气300m~3左右和商品有     

超声波预处理对秸秆发酵的影响

以秸秆为研究对象,在37℃条件下对不同的超声波强度和工作时间预处理的秸秆进行为期50 d的厌氧发酵试验,分析发酵过程中产气效率、累计产气量、pH值、CH4浓度等参数变化,并对秸秆微观结构进行电镜扫描,研究超声波预处理对秸秆微观结构的破坏以及厌氧发酵产气特性影响。试验结果表明:超声波预处理能提高秸秆发酵累计产气量和产气效率,平均单位日产气量由未经预处理的4.54 ml/(g.d)提高到经超声波处理后的6.86 ml/(g.d),提高了51.10%;超声波预处理对秸秆发酵pH无显著影响;沼气中平均甲烷浓度由未经预处理的43.83%提高到处理后的47.86%;最佳超声波预处理功率为225 W,处理时间为30 min。     

小型锅炉烟尘测试时锅炉出力的计算

锅炉烟尘测试时,必须对锅炉出力进行测试。但监测中,许多小型锅炉往往不具备相关的计量装置和仪表,为解决这一问题,文章提出了用烟气量和空气过剩系数来计算锅炉的出力的公式,在实际使用中,该方法简单易行,其结果和实测值具有很好的一致怀。     

Unerroric of control of mutual compliance of the efficiency of hydrogen engines of unmanned vehicles in the conditions of mass production

The issues related to the reliability of hydrogen engines of unmanned vehicles and increasing the efficiency of using hydrogen as fuel when using the method of its production during the decomposition of hydrogen-containing molecules of liquid-phase organic compounds in a plasma discharge under the action of intense ultrasonic exposure are considered. Experiments have shown that as a result of decomposition in the acoustoplasma discharge of liquid hydrocarbons, solid-phase carbon-containing products are formed, chemical transformations occur in the liquid phase and hydrogen-containing combustible gas is formed. Hydrogen-containing gas can be used as fuel immediately after synthesis, i.e. it does not require separation, since in addition to hydrogen it contains only impurities of CO₂ and water vapor. The purpose of the study is to formalize the basic conditions for tightening the control of mutual compliance with the efficiency of hydrogen engines of the same series in the conditions of their mass production. Methods of mathematical statistics and hardware-software modeling were used in the study. The term “unerroric of quality mutual compliance control” is introduced to describe a set of hardware and software tools for such control. The principle of in-depth testing of the technical condition of such engines of one series is described in a multidimensional formulation of the quality control problem for three of their operating parameters at once. The conditions for increasing the mutual correspondence of the measured values of such parameters in the conditions of serial production of hydrogen engines are formalized.     

中国煤炭地下气化技术的发展

本文综述了煤炭地下汽化技术的国内外发展现状,对我国“长通道、大断面”煤炭地下气化新工艺给予了技术经济评述,并提出了发展煤炭地下汽化技术的政策建议。     

Review of theory of distortion and disintegration of liquid streams

Linear and nonlinear analyses of the instabilities and distortion of liquid streams injected into a gaseous media are discussed. The various fundamental mechanisms and the predictive capabilities for the distortions are emphasized. Round jets, planar sheets, annular sheets, and conical sheets are discussed in detail. The balance between capillary and inertial forces is primarily examined. The method for simplifying the analyses in the case of thin liquid sheets is discussed. The capabilities for representing the droplet size distribution that follows the stream disintegration are outlined.     

MgO膨胀剂细度对MgO水化和水泥浆体膨胀的影响

基于《水工混凝土掺用氧化镁技术规范》中的Ⅰ型氧化镁（MgO）,研究了该型MgO膨胀剂（MEA）细度对掺粉煤灰水泥浆体膨胀性能的影响。即采用X射线衍射分析(XRD)及同步热分析（TG DSC）分析了掺MEA水泥浆体中MgO的水化性。结果表明,养护温度相同时,MEA的细度对水泥浆体内MEA中MgO的水化和水泥浆体的膨胀无显著影响,产生的膨胀均能补偿水泥浆体的收缩;MEA的细度可从试验设计采用的45 μm筛筛余15%左右增加到30%左右,这将有利于MEA生产企业的节能降耗。     

机车车轮多轴疲劳强度安全评定的研究

使用ANSYS8.0软件对高速列车车轮进行了三维有限元分析,计算出车轮在直线、曲线和道岔条件下牵引、制动共6种工况时孔边薄弱部位的应力,分别通过Mises等效平均应力方法、Sines平均主应力方法和应力分量中考虑平均应力方法计算出应力在极值位置时的等效应力幅、等效平均应力,从而进一步算出车轮的安全系数,对其疲劳强度进行评定,并对3种方法进行了比较研究。     

Constructal optimization of the geometry of an array of micro-channels

This paper documents the geometric optimization of an array of circular and non-circular ducts. The optimization was carried out numerically using finite volume method. As optimal dimensions were independent of the array configuration, the numerical simulation was performed on a unit cell. Numerical optimization for circular, square and isosceles right triangle cross-sections of channels was performed. Based on the results of this investigation, some correlations were proposed to predict the optimal hydraulic diameter and dimensionless heat transfer per unit volume. In addition to examining the effect of pressure drop on these parameters, it was showed that among the different geometries of this study, square cross-section has the most efficiency for a given volume. The numerical results of the present study were compared with approximate results reported in the literature which a good agreement was observed.     

固体热辐射Yong性能分析

本文对漫灰均温物体在常物性条件下对外辐射传热的Ｙｏｎｇ值计算建立了数学模型。通过与物体内能Ｙｏｎｇ公式的数值计算比较,得出了辐射能量的Ｙｏｎｇ值不大于内能Ｙｏｎｇ值的结论。从初步的热射Ｙｏｎｇ值计算公式发现。Ｙｏｎｇ与物体表面辐射率有关。     

Measurements of concentration distribution of hydrogen jet using deflection of center of the laser spot

The main purpose of this work is to propose a new method to evaluate the concentration distribution of the hydrogen jet by using a He–Ne laser through the jet. This research attempts to apply the expression of concentration Gaussian distribution, the refraction formula of inhomogeneous refractive index medium, and the concentration inversion function to disclose the displacement of the center of the laser spot at different heights in the gas jet. The spot images of the laser beam passing through the gas jet at three vertical heights z = 10d, 20d, 30d, and different radial positions are obtained. The radial spatial asymmetry of the gas jet is also found in the experiment. Finally, the calculated concentration distribution curve and the fluent simulation curve, it is found that the two results are very similar. Our findings show that the error between the concentration distribution of this method and the simulated concentration distribution reaches 2.43%.     

Heat of vaporization of mixtures

General expressions for the heat of vaporization of mixtures at constant pressure; at constant temperature; and at constant pressure, temperature, and composition are proposed. The last one is related to the liquid-vapor interface where steady vaporization or condensation is taking place. Numerical examples by the proposed expressions are shown for binary mixtures of HCFC22(R22) and (HCFC123(R123) © 1997 Scripta Technica, Inc. Heat Trans Jpn Res, 25(1): 12–24, 1996