细纱牵伸摩擦力界分析及工艺配置试验

探讨细纱罗拉加压与钳口隔距的工艺配置要求及牵伸区摩擦力界的合理性.通过分析中部摩擦力界对后区纤维与前区纤维运动的控制特点,并在CJ 14.5 tex和C 19.5 tex品种上对不同罗拉加压、钳口隔距配置下胶圈运转稳定性及成纱质量进行试验.结果表明:中罗拉和上下胶圈、销子所构成的中部握持钳口对牵伸效果起着关键作用,该区域摩擦力界的配置对前区牵伸效果产生直接影响,对后区牵伸也产生影响,同时影响胶圈运行状态.中罗拉适当增加压力,配合较小的弹性钳口隔距,使牵伸系统中部配置较强的摩擦力界,并使前后档罗拉加压与之协调,可在牵伸系统中获得较好的摩擦力界配置,对纤维的控制加强,有利于提高成纱质量.     

细纱牵伸器材及工艺配置对成纱质量的影响

为了降低生产成本,提高成纱质量,分析了细纱牵伸器材及工艺配置对成纱质量的影响,详细介绍了国产"V"型牵伸、气动加压、软弹性胶辊、新型上下销、中胶辊等新型纺纱器材在纺纱过程中的合理选用与配置,指出了新型牵伸器材在使用过程中应注意的事项,并进行了纺纱试验.结果表明:国产细纱机采用新型牵伸器材以及合理工艺配置,可以提高成纱质量.     

Submerged culture of Tricholoma matsutake mycelium in bubble column fermentors

Submerged culture of Tricholoma matsutake mycelium was carried out using two bubble column fermentors, a standard bubble column and an external-loop airlift column. The effects of the aeration rate and column type on culture performance in terms of the mycelia morphology, glucose consumption, cell yield, and growth rate were investigated. Morphologically, three types of pellets-large spherical, small spherical and filamentous-were observed depending on the aeration rate. On the whole, the standard bubble column gave a higher cell yield and a better growth rate than the airlift type. The maximum cell yield and growth rate attained at a superficial air velocity of 0.38 cm/s were superior to those obtained in a flask culture, suggesting that the bubble column fermentor has the potential to be used for submerged culture of T. matsutake.     

Influence of protein heat treatment on the continuous production of food foams

The influence of WPI heat treatment on the continuous production of food foams was investigated using a model food including xanthan. The temperature of heat treatment was increased up to 90 °C using a plate heat exchanger; a rotor–stator unit was used for aeration purpose. The aim was to determine the interplay between heat-induced protein denaturation and aggregation, and the process parameters of aeration operation: namely, rotation speed, residence time and operating pressure. Microstructure, texture and stability of 200% overrun foams were analysed. Experimental results demonstrated that foam microstructure, namely overrun and bubble size distribution, was governed by the process parameters of aeration and depended only slightly on thermal treatment. Conversely, foam stability was strongly improved by heat treatment. These trends agreed roughly with results obtained in a batch kitchen mixer, but batch methods remained unable to predict quantitatively the behaviours observed in continuous aeration operation.     

Biosynthesis of 1-Octen-3-ol and 10-Oxo-trans -8-decenoic Acid Using a Crude Homogenate of Agaricus bisporus: Reaction Scale Up

ABSTRACT: The enzymatic reaction that produces 1 -octen-3-ol and 10-oxo-trans-8-decenoic acid was successfully scaled up from a 1 -L to a 10-L bioreactor using a crude mushroom homogenate of Agaricus bisporus . For this non-Newtonian reaction broth, the agitation rate was considered the most important controlling factor for the scale up. An agitation rate of 600 rpm, for an aeration rate of 0.44 m³/m³/h, was found to be the minimum to maintain the yield constant for the 1-L reactor. Subsequently, the agitation rate for the 10-L reactor was determined using 2 different approaches: a constant power per volume of liquid and a constant volumetric mass transfer coefficient (k_La). The constant power per volume of liquid approach predicted an agitation rate of 364 rpm that resulted in being too low to maintain the same yield obtained with the 1-Lreactor. Measurement of the kLa for the 10-Lreactor, at 364 rpm and an aeration of 0.44 m³/m³/h, produced a value of 11.7/h, thus confirming that the reaction in the larger reactor was oxygen-deprived. Therefore, the use of constant volumetric mass transfer coefficient (kLa) strategy was used instead. k_La was experimentally determined at different agitation rates for the 10-L reactor. It was found that 750 rpm produced a k_La of 40.2/h. Confirmatory reactions were run in both reactors with the same batch of mushrooms, and the results were equivalent, thus indicating that was a good criterion for scaling up this process.     

Development of a bioreactor suitable for embryogenic rice callus culture

Embryogenic rice calli induced from mature rice (Oryza sativa L., Sasanishiki) were cultured in a jarfermentor with disk turbine impellers, an air-lift reactor, and a turbine-blade reactor (TBR(R)), and the effects of agitation were investigated. In all cases, the growth inhibition was observed, though a slightly improved regeneration frequency was obtained in the TBR. To overcome the growth inhibition, small cubes of polyurethane foam were used as immobilization supports in the TBR culture. Supports accumulated around the cylindrical stainless-steel mesh in the reactor and rice calli were observed growing in them. Polyurethane foam with an average pore size of 1.3 mm gave the maximum ratio of immobilized cells during 1-week culture. When 5- or 10-mm cubes were used, supports were observed floating on the medium surface, but 3-mm cube supports accumulated uniformly around the stainless-steel mesh and were found to be suitable for the immobilized culture of rice calli. Three-millimeter cube supports corresponding to 5% by volume were added to 600 ml medium in the TBR and the effects of the agitation speed on the cell growth and regeneration frequency were investigated. At all the agitation speeds examined, no significant decrease in either the cell growth or the regeneration frequency occurred. From these results, it was concluded that the TBR is a suitable reactor for the propagation of embryogenic rice calli and that immobilization supports with 1.3 mm of average pore size are effective in preventing hydrodynamic stress as well as in supplying nutrients to the immobilized calli.     

细纱上销与下销的优化配置

介绍了新型尼龙上销、下销的几何特点,针对上销与下销配置不当在纺纱中出现牵伸不良的现象,对两种平面宽度下销和三种钳口面宽度上销进行了优化配置纺纱试验,并通过适当调整后区牵伸倍数、胶辊袁面粗糙度参数,实现了顺利纺纱,取得了较好的纺纱质量.     

Enhancement of l(+)-lactic acid production using acid-adapted precultures of Rhizopus arrhizus in a bubble column reactor

88 g/L lactic acid was produced from waste potato starch (equivalent to 100 g/L glucose) in a bubble column reactor using appropriate acid-adapted precultures of Rhizopus arrhizus. Further experiment showed that repeated dilution of cultures caused the decrease of lactic acid concentration and productivity due to formation of large fungal pellets.     

无载体固定化米根霉半连续发酵产L－乳酸工艺研究?

为了选择米根霉半连续发酵产L-乳酸工艺参数,通过单因素试验和正交试验,对接种量、CaCO3添加时间、温度、装液量及转速进行了优化,并采用培养基重复发酵,建立米根霉半连续发酵工艺。其中摇瓶半连续发酵条件为：孢子接种量4%,种子接种量10%,发酵开始时添加CaCO3,装液量为20%～30%,0～36h时发酵温度28～30℃、36～72h时发酵温度32～34℃,转速200r/min。7L磁力搅拌发酵罐半连续发酵工艺条件为：搅拌转速为300r/min,通气量为1.25L/(L·min),温度为32℃。发酵罐重复发酵稳定,产L-乳酸最高达到86%。为米根霉半连续发酵产L-乳酸的工业化生产提供了研究基础。     

Assessment of the energy dissipation parameters inside the draft tube of a liquid spout-fluid bed

Spouted beds are fluid-particle contactors in which the fluid is introduced centrally through a nozzle instead of a distributor plate, resulting in a regular particle circulation pattern. To assess the suitability of such sytems to environmental engineering applications such as filter backwashing and biofilm systems, a priori knowledge of the energy dissipation parameters is essential. A new model is developed for evaluating the energy dissipation parameters inside the draft tube of spout-fluid beds. The shear stress, velocity gradient, and turbulence fluctuation parameters in the draft tube of a liquid spout-fluid bed are calculated with the help of an energy equation for flows carrying suspensions and the experimentally determined pressure losses inside the draft tube and compared with results for particulately fluidized beds. A spout-fluid bed with a draft tube provides higher shear stress inside the draft tube than a fluidized bed. The mean velocity gradient in the draft tube is comparable to and higher than in a fluidized bed and increases with solids fraction. The turbulence dissipation coefficient decreases very slightlywith increasing solids fraction for both systems. Consequently, according to the model calculations, a spout-fluid bed with a draft tube can be an alternative to the classical fluidized bed filter backwashing system.     

Continuous production of wine vinegar in bubble column reactors of up to 60-litre capacity

This paper describes the development of a continuous acetic acid fermentation process for the production of wine vinegar in bubble column reactors of up to 60 l capacity. To determine appropriate fermentation conditions a study of the influence of residual ethanol concentration, inlet flow rate and aeration was carried out using a 6-l laboratory reactor, white table wine as fermentation medium, a temperature of 30 °C and an air flow rate of 0.125 min^-1 (vvm). The concentration of acetic acid obtained in the continuous wine vinegar production ranged from 91 g/l at 28.6 ml/h to 28 g/l at 154.1 ml/h by increasing the inlet flow rate. As expected, the biomass decreased as well, from 208 mg/l to 106 mg/l. The maximum acetification rate was observed in the range 85-110 ml/h, corresponding to a value of about 1.1 g/l/h. A further increase in the flow rate produced a slight decrease in the acetification rate. Best yields, between 94.5 and 94.7%, were obtained in the flow rate range of 60-75 ml/h. The acetification rate was improved only by about 10% by increasing the aeration from 0.125 to 0.250 min^-1. The continuous wine vinegar production was scaled up from the laboratory fermentor to a 60-l pilot acetator. During the steady state (residential time >6), with an inlet flow rate of 950 ml/h, temperature of 30 °C and aeration of 0.250 min^-1, the following parameters were obtained: acetic acid concentration 72 g/l, overall productivity 1.41 g/l/h and yield 94.2%.     

棉结和杂质测试仪结构设计改进

为了解决棉结和杂质测试仪在试用时出现的机械传动不稳、噪声大、牵伸挂花、缠棉、胶辊被卡、棉网飘摆、光源角度调整不便等问题,对其原始样机的机械传动部分、棉条牵伸部分、胶辊压紧方式、背景板距离、光源调整机构进行改进;改进后的棉结和杂质测试解决了前期出现的问题,达到了要求,为纺织企业提供了一个新的测试仪器,操作简单;但在牵伸结构的可靠性和光源调整方面还需进一步探讨与改善。     

Hansenula anomala转化葡萄糖生产阿拉伯糖醇的研究

对Hansenula anomala转化葡萄糖生产D-阿拉伯糖醇的反应条件进行了研究。高供氧量有利于阿拉伯糖醇的生成。在一定范围内,葡萄糖初始浓度越高,阿拉伯糖醇的产量也随之明显提高。并通过正交实验,确定了最佳发酵条件为(g/L):葡萄糖500,酵母膏2,蛋白胨2,CaCl20.5,(NH4)2SO45,MgSO41,KH2PO43,pH5.0;发酵温度30℃,装液量15～20mL/500mL三角瓶,发酵时间263h。阿拉伯糖醇浓度为245.97g/L,转化率为0.49g阿拉伯糖醇/g葡萄糖,平均反应强度0.935g/Lh。     

灰树花深层发酵富集锌元素的研究

灰树花是药食两用真菌,富含多糖、氨基酸和矿物元素,可用液体深沉发酵大规模生产。对锌含量、马铃薯、葡萄糖、麸皮、接种量等对灰树花的影响以及对灰树花深沉发酵富集锌元素的能力进行了研究。结果表明,当马铃薯含量为250 g/L,葡萄糖为30 g/L,麸皮为20 g/L,锌含量50 mg/kg且接种量为20%时菌丝体生长较好。当锌含量大于1 000 mg/kg时,菌丝体的生长受到抑制;当锌含量达到1 500 mg/kg时,菌丝体生长极其缓慢。总之,锌含量对菌丝体的生长影响显著,其他因素对菌丝体生长的影响不大。另外,从灰树花的富锌能力来看,当锌含量为50 mg/kg~1 500 mg/kg时,菌丝体的富锌能力为124 mg/kg~2 555 mg/kg。所以,综合考虑生长情况和富集情况,选择马铃薯为200 g/L,葡萄糖为24 g/L,麸皮为30 g/L,锌含量为500 mg/kg,接种量为5%时,菌丝体的富锌能力最好。     

软水蓼不同目数超微粉体溶出物的化学成分分析

为分析软水蓼不同目数粉体溶出物的化学成分。采用超高效液相色谱-四级杆飞行时间质谱(UPLC-Q-TOF/MS)对软水蓼不同目数粉体化学成分进行初步分析。结果表明:软水蓼不同目数粉体的体积粒径大小随目数增加而降低;面积平均粒径从50目下降至300目时最低,再逐渐增加;粉体颗粒表面随目数增加越来越光滑,原药材特征越来越不明显;不同目数粉体溶出物中分离鉴定出17个化合物,其中黄酮类化合物9个、苯丙素类5个、有机酸、多糖及鞣质各1个,其中苯丙素类化合物Vanicoside C在200目和300目粉体中没有检测出;黄酮类化合物的峰面积值从过50目筛的粉体逐渐升高,在120目出现较高的峰面积值,随后从200~300目逐渐降低,再到500目时呈逐渐升高趋势,其中槲皮苷的相对峰面积值最高为47.11%;苯丙素类化合物峰面积值从50目下降至300目最低值,随后呈上升趋势,其中Vanicoside B相对峰面积值最高为47.79%,为明确活性化学成分作用机制及药效物质基础的阐明提供了重要依据。     

Low Pressure Gel Chromatographic Separation of Oligosaccharides

A method is described for the separation and analysis of oligosaccharides by gel chromatography, using Bio-Gel P-2, 200–400 mesh and Bio-Gel P-4, 200–400 mesh. Resolution of malto-oligosaccharides containing up to 13 glucose residues was obtained on both the P-2 and the P-4 columns. This resolution is slightly lower than that obtainable using the finer minus 400 mesh gel. However, when the two columns were connected in series, resolution of oligomers containing up to 15 glucose residues was obtained. This resolution is comparable to that obtainable on a single P-2 minus 400 mesh column. Improved resolution of lower oligomers was obtained by recycle gel chromatography on the P-2 column. Some of the practical difficulties associated with the operation of a minus 400 mesh gel column were avoided as high pressure is not required to operate the 200–400 mesh gel columns.     

Medium optimization using mathematical statistics for production of β-Carotene by Blakeslea trispora and fermenting process regulation

Optimization of medium components for enhancement of β-carotene production by Blakeslea trispora was achieved using mathematical statistics. Optimum concentrations of components using Plackett-Burman design and response surface methodology (RSM) were d-glucose 7.16%, wheat bran extract 4.08%, MgSO₄ 0.04%, soybean oil 3%, thiamine 0.01%, soybean meal 1%, and KH₂PO₄ 0.2%. Maximum production of β-carotene using optimized medium was 643 mg/L in a shake flask. A predicted value of 669 mg/L was based on results of an RSM regression. The optimum aeration rate of 1.5 vvm produced 866 mg/L and the optimum agitation speed of 100 rpm produced 975 mg/L of β-carotene. The t of a quadratic model using regression derived coefficients was significant. Maximum production of β-carotene using the optimized medium in a stirred tank reactor (10 L) at an optimal aeration rate and an optimum agitation speed with addition of 0.1%(v/v) β-ionone was 1,357 mg/L.     

花生发根培养条件的优化

利用单因素实验和正交设计研究了培养基中激素、碳源、氮源、磷酸盐、初始pH等对鲁花11号花生发根生长的影响。结果表明,花生发根的最适基本液体培养基为无激素的MS培养基;培养基中加入NAA、6-BA、IBA等三种激素,在不同程度上抑制发根的生长;花生发根培养最适条件为：碳源为1.5%蔗糖、氮源含量与标准MS培养基相同、磷酸盐为3.75mmol/L、初始pH为6.1。100μmol/L水杨酸（SA）可以提高花生发根白藜芦醇苷合成分泌以及白藜芦醇的合成。     

利用合成煤气经厌氧发酵生产有用的燃料和化学品

本文总结了由合成煤气经厌氧发酵生产氢气、甲烷、乙醇、乙酸等有用的燃料和化学品,并比较了各种不同的生物反应器(包括固定化细胞生物反应器),如连续搅拌罐反应器、充填气泡柱式反应器和涓流床生物反应器等的操作性能。     

高效节水节能的内循环流态化水冷器技术

内循环流态化换热器的应用效益相当高，但是还不够完善，较长时期运行后可能发生流态化底室筛板部分筛孔堵塞和出口室沙子跑失的问题。中重点研讨了采用泡罩板取代筛板解决堵塞问题后出现的均匀性问题，多方案优化的结果是采用较大直径的泡罩，并且加装一块大孔均布板，以满足稳定运行的要求。研制成功的传热管管口档罩，不仅具有防止粒子跑失的功能，而且还具有一定的流速调匀作用和防止低流速管创新粒子倒流的稳定功能。