捻制设备收线轮直径范围的调整

阐述打滑器打滑率的概念，给出在收线轮直径已调整条件下，收线传动比应满足的一般关系式，提出了要满足打滑器正常打滑，重新设计收线工字轮直径时必须符合的条件。     

机器参数对皮圈打滑的影响

由于缺少一种积极有效的方法来控制下皮圈向上皮圈的传递运动,故皮圈打滑的现象会发生在环锭细纱机的每一个锭位处。一般来说,上皮圈的速度总慢于下皮圈,这是引起皮圈打滑的原因所在。当上、下皮圈之间有纤维存在时,皮圈速度的差异会增加。皮圈打滑使纤维在皮圈区域的运动不可控,导致纱线质量恶化。皮圈打滑有两种类型,皮圈和皮圈间的打滑,以及下皮圈的打滑。原料、摇架压力、隔距大小、粗纱喂入量和后区牵伸等都会影响皮圈的打滑。     

打滑地层金刚石钻头制造工艺研究

分析了打滑地层打滑的原因;研究了采用弱包镶钻头钻进打滑地层的防滑机理、金刚石钻头胎体分层设计在破碎硬岩时胎体磨损状态。应用研究表明：采用了胎体分层设计的弱包镶金刚石新型钻头,在打滑地层钻进时,钻进效率良好,钻头寿命也得到明显提高。     

带式输送机输送带打滑现象的防止

介绍带式输送机输送带打滑的原因、后果及防止打滑的措施和办法。     

中型袋自动立式包装机牵膜打滑问题的解决

本文在分析中型袋自动立式包装机牵膜打滑形成机理的基础上，介绍了对同步齿形带进行的特殊工艺处理以防止打滑的具体措施     

提高金刚石钻进“打滑”岩层生产效率的措施

自从我国推广应用金刚石钻进技术以来，就如何提高金刚石在钻进坚硬、致密、弱研磨性岩层(“打滑”岩层)的效率进行了许多研究。文章比较了电镀和孕镶金刚石钻头在该类地层防“打滑”的研制情况，确定孕镶钻头是解决“打滑”岩层并提高生产效率的最佳选择。     

进一步分析钢丝拉拔过程中滑动量的变化并探讨最佳水箱拉拔方法

<正> 多道次滑动式水箱拉丝机的钢丝拉拔是将塔轮、模子、钢丝均浸没在肥皂液中使钢丝在塔轮各鼓轮面上进行打滑来实现的。打滑量的大小是由预先设计的拉拔工艺来决定的,并在一定程度上反映了工艺设计的优劣。过大的打滑量对设备的动力消耗,塔轮     

浅谈皮带机打滑原因和检修

本文在对带式输送机工作运力分析的基础上,对带式输送机打滑的原理进行了分析,针对打滑产生的原因,进而对带式输送机的检查进行了分析,研究结果对带式输送机的研究和改进以及维修具有指导意义。     

数字式打滑率测定仪

多年来,国内对拖拉机驱动轮打滑率多用数驱动轮圈数的方法进行测量,也有用接触式或非接触式开关通过计数的办法进行测量,但都不太配套,而且精度不高,不能直接得到测量结果。我们采用集成电路研制了一种直接数字显示的打滑率测定仪如图1,并配有接近开关式的传感器,可以独立地测量打滑率。     

6/600合绳机摩擦打滑器的改造

1　传统的摩擦打滑器1.1　传统的摩擦打滑器的结构其结构如图 1所示。图 1　传统的摩擦打滑器结构1.联接装置　 2 .铜套　 3.注油孔4.锥齿轮　 5 .闸皮摩擦轮1.2　该结构在使用中存在的问题(1)图 1中使用的铜套在运行中采用手工注油润滑 ,由于注油孔距注油点 (轴端 )长达 4 5 0     

Encapsulation of food ingredients

Microencapsulation is a relatively new technology that is used for protection, stabilization, and slow release of food ingredients. The encapsulating or wall materials used generally consist of starch, starch derivatives, proteins, gums, lipids, or any combination of them. Methods of encapsulation of food ingredients include spraydrying, freeze‐drying, fluidized bed‐coating, extrusion, cocrystallization, molecular inclusion, and coacervation. This paper reviews techniques for preparation of microencapsulated food ingredients and choices of coating material. Characterization of microcapsules, mechanisms of controlled release, and efficiency of protection/ stabilization of encapsulated food ingredients are also presented.     

Water–disaccharides interactions in saturated solution and the crystallisation conditions

This paper reports solubility data and measurements of viscosity of the saturated aqueous solutions of sucrose, maltitol, and trehalose. Likewise, the metastable zone width and velocity of nucleation of the three disaccharides are compared. The narrowest metastable zone is observed for maltitol and the largest for trehalose. Such behaviour is due to a higher affinity of trehalose for water. Moreover, the crystallisation of anhydrous disaccharides in aqueous solution necessitates that hydration water be removed and evacuated from crystal integration surface to the bulk of solution to allow the growth of crystals. This step of disassociation and diffusion of hydration water proves to be the controlling step of the crystallisation process. Structural features at the origin of the differences between the three sugars are studied by FTIR spectroscopy. Modifications of frequencies and intensities of the vibrations around the glycosidic bond are interpreted in terms of conformational flexibility. Arguments like H-bond strength or conformational flexibility of the two monomers around the glycosidic oxygen were evoked as possible explanations of the behaviour of disaccharides. Likewise stability of hydration of the disaccharides is derived from the interpretation of FTIR spectra. These structural features help in interpreting the differences in crystallisation conditions and to hypothesize about the cryoprotective ability of the studied molecules.     

Depth of concussion in cattle shot by penetrating captive bolt

The prevalence of shallow depth of concussion following captive bolt shooting was assessed in 1608 cattle at an abattoir. Depth of concussion was determined in each animal from physical collapse, presence or absence of corneal reflex, normal rhythmic breathing, eyeball rotation, and whether the animal was re-shot. The presence of nystagmus and the absence of tongue protrusion were also monitored as potential indicators of a shallow depth of concussion, and simultaneous noise measurements assessed whether loudness of gun discharge was linked to concussion depth. The prevalence of a shallow depth of concussion was 8% for all cattle and 15% for young bulls. Nystagmus was associated with other indicators of a shallow depth of concussion. Absence of tongue protrusion was not associated with depth of concussion, but could serve as a useful indicator of jaw relaxation and insensibility following exsanguination. Soft-sounding shots (111 dB) when using 4.5 gr cartridges were associated with shallow depth of concussion.     

39—THE FLOW OF LIQUID FROM A JET THROUGH A COMPRESSIBLE POROUS LAYER. PART III: THE CHARACTERISTICS OF LIQUID FLOW THROUGH A COMPRESSIBLE LAYER OF LOOSE WOOL

The effects on the conditions of flow of the surface and configurational properties of the fibres in a compressible porous layer are discussed. The characteristics of a layer of wool are evaluated, and its compressibility is determined. It is shown that, when a liquid of initial uniform pressure flows through a compressible porous medium, the pressure gradient within the medium increases with the distance of flow. The resulting pressure drop is found to depend on a function of the ratio of the downstream to the upstream porosity of the compressible medium. Experimental results are reported for permeable flow through various layers of loose wool; these indicate that, when the flow is disturbed turbulent, the pressure drop through the layers is proportional to the square of the filter velocity. This result is not readily apparent from the graphs of pressure drop against filter velocity because of the compressibility of the fibres.     

Headspace solid‐phase microextraction analysis of artificial flavors

Using a non‐equilibrated solid‐phase microextraction/gas chromatography/mass spectrometry technique, differentiation between a wide variety of types and examples of artificial flavors has been demonstrated. Addition of an internal standard to the samples, as received, allowed for the calculation of yields on a µg g^?1 basis for the majority of headspace volatiles. The relative standard deviation values expressed as percentages were between 3 and 5%. The precise nature of the approach coupled with the compound identification capacity of the mass spectrometer afforded the capability to easily differentiate between multiple sources of artificial flavors. With a total analysis time of approximately 30 min and the absence of solvent, this approach has the capability of detecting and quantifying the presence of the low‐molecular‐weight solvents often used in the preparation of artificial flavors. Such a capability represents a distinct advantage over more conventional methods of solvent dilution. Results from conventional gas chromatography/mass selective detector analyses are contrasted and compared with the results obtained from the headspace SPME approach. Copyright © 2005 Society of Chemical Industry     

21—THE ACETYLATION OF COTTON

An account is given of a study of the effect of the amount of activating agent, the temperature, the catalyst, and the diluents used in the acetylation of cotton with perchloric acid as catalyst. Sulphuric acid was compared with perchloric acid as a catalyst. The effects of traces of water, the amount of acetyl chloride, and the rate of acetylation were studied in the acetylation of cotton with acetyl chloride and pyridine. The conditions in all cases were such that the acetylated cotton retained its fibrous form.     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Biodegradation of genetically modified seeds and plant tissues during composting

BACKGROUND: The increasing global market of genetically modified (GM) crops amplifies the potential for unintentional contamination of food and feed with GM plants. Methods proposed for disposal of crop residues should be assessed to prevent unintended distribution of GM materials. Composting of organic material is inexpensive and location‐independent. The objective of this study was to determine the effectiveness of composting for disposal of GM plants in terms of reducing seed viability and promoting the degradation of endogenous as well as transgenic DNA. RESULTS: Duplicate samples of corn kernels, alfalfa leaves, and GM canola seeds, meal and pellets were sealed in porous nylon bags and implanted in duplicate 85 000 kg (initial weight) feedlot manure compost piles. Samples were collected at intervals over 230 days of composing. Canola seeds and corn kernels were not viable after 14 days of composting with temperatures in the piles exceeding 50 °C. In all samples, PCR analyses revealed that plant endogenous and transgenic fragments were substantially degraded after 230 days of composting. Southern blotting of genomic DNA isolated from canola seeds identified differences in the persistence of endogenous, transgenic, and bacterial DNA. CONCLUSION: Composting GM and non‐GM plant materials with manure rendered seeds non‐viable, and resulted in substantial, although not complete, degradation of endogenous and transgenic plant DNA. This study demonstrates that composting could be effective for disposing of GM crops in the event of their inadvertent entry into the food or feed chain. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd