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41.
为解决Coolplus在纯纺针织物编织、染色过程中容易出现的问题.依据Coolplus纤维的性能和特点,结合生产实践探讨了纯Coolplus纤维单面提花针织物的织造及染整工艺,并且给出了具体生产工艺以及常用的染料、助剂的选择方法. 相似文献
42.
仓式静态连续好氧堆肥发酵工艺的水气研究 总被引:2,自引:0,他引:2
采用仓式静态连续好氧堆肥发酵工艺,通过建立水平衡体系,系统地研究了水分对整个发酵工艺的影响,得出了仓式静态连续好氧堆肥发酵具有工艺简便,热交换快,水气蒸发量大等特点;好氧堆肥发酵过程中发酵温度保持在65℃左右,含水量控制在45%~55%有利于有机物降解,垃圾堆肥可在40~50d腐熟;静态连续好氧一次堆肥发酵物料的含水量需控制在35%以下,机械自动分选(类)筛分效率高,筛分率在90%~95%,垃圾减容在50%~60%.二次堆肥发酵物料的含水量需控制在25%~30%,机械除杂(碎石、碎玻璃等)效果好,有机肥中杂质含量低于0.8%.静态好氧二次堆肥发酵可以用垃圾渗沥水补充水分,达到资源循环再利用,可实现污水零排放. 相似文献
43.
掺灰膨胀土的膨胀特性试验研究 总被引:3,自引:0,他引:3
通过生石灰对膨胀土的改性作用,在相同初始含水率的条件下,比较改性前后膨胀力、膨胀率的变化趋势,寻求最佳掺灰率;分析了膨胀力与初始含水率,膨胀率与初始含水率以及终止吸水量与初始含水率等关系. 相似文献
44.
LDPE/SiO2复合膜性能的研究 总被引:1,自引:0,他引:1
以LDPE/EVA(质量比为90/10)为基材,添加SiO2制备了LDPE/SiO2复合膜,对该复合膜进行了力学性能,透气、透湿性能和结晶性能的测试.结果表明:添加SiO2后,LDPE/SiO2复合体系的力学性能有所下降;O2和CO2气体透过系数先增加后下降;水蒸气透过系数先增加后趋缓;LDPE复合体系的成核速率和结晶速率增加,结晶温度略有提高.形成的球晶尺寸变小,数量增多. 相似文献
45.
季冻区高速公路路基冻害调查及试验观测 总被引:5,自引:1,他引:4
在对吉林省几条高速公路进行的野外冻害调查、现场观测和室内冻胀、水分迁移模拟试验的基础上,依据取得的野外资料和室内试验数据,对季冻区高速公路路基冻害的原因和影响因素进行分析和探讨;对冻害与水分关系、路基冻害水分来源、水分迁移特征以及由于路面底基层二灰土性能恶化失效导致的道路翻浆等问题进行了深入研究.同时利用本项目综合研究的特点,将竖管法毛细水沿高度分布的研究资料与由冻胀试验揭示的各种冻胀率——含水量变化规律有机结合起来进行分析,从而得到了毛细水冻害有效高度,试验结果表明:规范值相对试验值在一些情况下偏低,有的低很多,对路基防冻抗冻设计不利.研究成果对公路路堤最小高度设计和挖方段防冻处理深度设计等防冻措施的采用有实际意义. 相似文献
46.
A three‐dimensional braided carbon fiber–epoxy (C3D/EP) composite was prepared by the vacuum‐assisted resin transfer molding (VARTM) technique. Its moisture absorption behavior under different media was characterized and compared with a unidirectional composite. Similar to the unidirectional composite, diffusion in the 3D composite obeys Fick's second law of diffusion when immersed in distilled water and phosphate‐buffered saline. In HCl and NaOH solutions, no Fickian behavior was observed. The similarity between the unidirectional and 3D composites suggests that fiber structure does not change diffusion pattern. However, the two composites showed different diffusion parameters (k, D, and Me) in each medium studied. The 3D composite showed lower k, D, and Me values because of its stronger hindrance effect to transport of moisture molecules. Diffusion in PBS is slower than that in distilled water because of the presence of heavy ions, but the diffusion pattern remains unchanged. In HCl, the diffusion behavior of the two composites cannot be described by Fick's law. In addition, the k value calculated from the initial linear part of the moisture sorption curve is much lower than that in distilled water. Diffusion in NaOH is unusual; the uptake initially increases rather rapidly but quickly drops, which is likely caused by the extensive solubility of the polymer matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 507–512, 2005 相似文献
47.
The response of lentil grown under rainfed conditions to directly applied and residual phosphorus (P) was described by a modified Mitscherlich equation, accounting for the effects of rainfall on (1) potential yield, and (2) the availability of soil-P to the crop. The response of lentil yield to directly applied and residual P was studied in two-course cereal–lentil rotational trials under rainfed conditions in a Mediterranean-type environment. Cereal crops were grown at different P application rates during 4 growing seasons at 3 sites, representing different rainfall zones in northwest Syria. Lentil (Lens culinaris Med.) was grown during 4 seasons at the same sites, each lentil crop following a cereal crop. In 3 out of 4 lentil-growing seasons, additional P was applied to lentil in subplots to compare the residual and direct effects of P application. The initial contents of extractable soil-P (P-Olsen) were low at all sites, in the range of 2–5 ppm P. Under the conditions of the experiments, lentil appeared to benefit slightly more from P applied to the preceding wheat crop (residual P) than from directly applied P. It is shown that the modified Mitscherlich equation could be used as a basis for P fertilizer recommendations for rainfed farming. As for lentil, it was concluded that a single application of P to the wheat crop in a wheat/lentil rotation could reduce the cost of lentil production, without reducing lentil yield. 相似文献
48.
49.
The object of the present study was to investigate the effect of superimposed dynamic and static stresses on mechanical and thermal properties of some epoxy adhesives. It was found that combinations of shear creep and torsional oscillations, applied simultaneously to adhesive joints at temperatures within the glassy range of the adhesive, led to strengthening of the joints in shear and to an increase in the glass transition temperature of the adhesive. Similar loading stresses applied at temperatures close to the Tg of the adhesive, led to opposite effects on the above mentioned properties of the joints. The width of the glassy-rubbery transition of the adhesives increased, in the whole range of temperatures used in this study and for all epoxy compositions, as a result of subjecting the joints to superimposed dynamic and static stresses. The broadening of the glass transition was interpreted as a result of the stiffening of polymer network during the combined stressing experiments. A linear relationship was found between the area of endothermal peaks in the first DSC scan of specimens subjected prior to test to superimposed dynamic and static stresses at temperatures below Tg, and the shear strength of the joints. In agreement with this observation and with literature data, a linear relationship was revealed also between the glass transition temperature of the resins (measured in the first DSC scan) and the shear strength of the joints. Based on experimental observations and on some literature information, it was suggested that the strengthening of the joint, as well as the changes in thermal properties of the adhesives, are mainly due to physical processes, such as short-range orientation of network chains and an increase in intermolecular interaction between highly polar sites of the network. The possibility that superimposed stressing led to changes in chemical crosslinking was discussed but it seems that no such reactions occurred. 相似文献
50.
应用一步流动法快速测定土水特征曲线试验研究 总被引:1,自引:0,他引:1
实验室常用压力板仪进行常规试验测定粉土土水特征曲线(SWCC),需耗费数月时间,效率不高。对快速测定粉土SWCC进行了试验研究:采用压力板仪对粉土试样开展一步流动法试验;同时,用Hydrus-1D建立一维水分运移模型;结合模型对干密度为1.78 g/cm3粉土试样中溢出水量随加压时间的关系曲线进行拟合,并得出VG模型中难以实测的参数α和n;根据参数反算出粉土试样SWCC并和压力板仪常规试验的SWCC进行对比。为了消除试验中加载压力过大可能造成的固结对试验结果的影响,还对干密度为1.65 g/cm3的粉土试样进行固结试验使其干密度增大为1.78 g/cm3,再对固结后粉土试样分别进行常规试验和一步流动法试验。对由两种试验得到的固结粉土的SWCC与初始干密度1.78 g/cm3粉土由两种试验实测的SWCC进行了比较。结果表明:① 一步流动法试验拟合的SWCC与常规试验实测的SWCC重合度高;② 一步流动法试验具有快速性和有效性;③ 由Hydrus-1D建立的一维水分运移模型得出的SWCC与常规试验实测的SWCC接近;④ 一步流动法试验结果不会受到固结的影响。 相似文献