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91.
低温化学镀镍-磷合金工艺的研究   总被引:1,自引:0,他引:1  
通过对比低温环境下几个配方工艺,提出了一个在镀速、耐蚀性等方面均表现较好的工艺配方,同时发现了一种有优越作用的复合配合剂。  相似文献   
92.
针对现有油菜基质块苗移栽机开沟装置作业存在沟宽稳定性差、沟底面平整度低、土壤扰动大等现象,导致立苗率低、覆土作业难度大等问题,基于船式开沟器腔体大以及芯铧式开沟器作业构建宽苗床、平沟底特点,结合类铧式曲面衔接过度,设计了一种适用于油菜基质块苗移栽机苗床构建的苗床带整备装置。建立了土壤与整备装置互作力学模型,确定了苗床带整备装置构建稳定苗床的主要结构参数。以整备装置作业速度、作业深度、类铧式曲面前端宽度、刃口角为因素,以土壤扰动量、沟宽变异系数为评价指标,利用EDEM开展四因素三水平二次正交组合仿真试验,试验结果显示:作业深度为41 mm、作业速度为0.52 m/s、类铧式曲面前端宽度为40 mm、刃口角为61o时土壤扰动量较小且沟宽变异系数较小;较优参数组合下台架试验得出土壤扰动量为13.01 cm2,沟宽变异系数8.52%。田间试验结果显示:安装在移栽单元上的苗床带整备装置相较船式开沟器的载苗基质块立苗率增加2.09百分点,沟宽变异系数减少13.3%,土壤扰动量减少20.9%,沟底面紧实度增加28.7%,满足油菜基质块苗机械移栽苗床构建要求。  相似文献   
93.
淡水鱼的连续式鱼鳞去除方法   总被引:4,自引:3,他引:1  
为研究连续式鱼鳞的去除方法,以鲢鱼、鳊鱼、鲤鱼为试验对象,提出了一种以弹簧为主要去鳞结构的去鳞刷,并以弹簧外径、去鳞刷转速与去鳞刷直径等为主要因素,通过自制去鳞试验台研究了其对淡水鱼去鳞率和鱼体损伤的影响,表明弹簧外径、去鳞刷直径对淡水鱼去鳞率有显著影响,对鱼体损伤感官评价得分影响不显著,去鳞刷转速对去鳞率和鱼体损伤感官评价得分均有极显著影响。不同种鱼,其各自适宜的弹簧外径、去鳞刷直径与去鳞刷直径有所不同。确定了白鲢去鳞时弹簧外径、去鳞刷转速、去鳞刷直径的最优参数组合,即弹簧外径21 mm、去鳞刷转速1 120 r/min、去鳞刷直径90 mm。该研究可为连续式去鱼鳞机的研制提供依据。  相似文献   
94.
以黑龙江省齐齐哈尔市甜菜生产区为主,提出无公害甜菜高产栽培技术,确保本地区甜菜产量和产品质量的提高,为无公害农产品甜菜生产向标准化和集约化方向发展提供科学依据,达到甜菜丰产丰收的目的。  相似文献   
95.
Chemical plating is one of the metallising treatment processes for fibrous materials that can produce unique textile properties. It poses a great potential for textile products in application aspects including functional and decorative effects. This study has investigated the operation condition and resultant performance of using chemical silver plating on polyester fabric. The silver-plated polyester fabric exhibited a specific protective function and novel appearance if optimum chemical plating condition was chosen. Furthermore, the fabric design practice employed by this chemical technique with design approach had achieved the diverse effects.  相似文献   
96.
A 7-month-old, 180-kg, female foal was presented with open diaphyseal fracture of the left third metacarpal bone. The fractured limb was stabilized preoperatively with external coaptation. Open reduction and internal fixation were done using 4.5-mm broad dynamic compression plate, which was applied in a neutralization manner. Postoperatively, external support with padded bandage reinforced with gutter splint made of fiber glass was provided. The incisional infection and the contaminated wound on medial aspect of the metacarpal were managed with regular dressing. Complete radiographic union and functional recovery were noticed by 4 months postoperatively. Open diaphyseal fractures can be managed by proper preoperative fracture stabilization, wound management, and fixation methods using bone plate and external coaptation.  相似文献   
97.
Glycated proteins are considered as one of the factors involved in the pathogenesis of diabetic complications, including nephropathy. These proteins are formed endogenously under conditions of hyperglycemia, as well as being provided with food containing sugars, which was subjected to high temperature. Examples are egg products. One of the proteins found in eggs in a relatively high concentration is chicken cystatin (ovocystatin). It is now believed that some proteins can passage the intestinal epithelium by transcytosis directly into the bloodstream. Thus, glycated protein present in food can be an additional source of glycotoxins. The aim of this study was to compare the affinity of native and glycated cystatin to the brush border membranes of rat kidney. Kinetic analysis was performed with surface plasmon resonance technique using sensor chip L1. Dissociation constants for native and glycated cystatin (Kd) were 2.76 μmol/L and 3.82 μmol/L, respectively. The results of our study indicate that glycation only slightly affects binding of cystatin to brush border membranes. This suggests that glycated cystatin and other glycated proteins may also be efficiently taken up in the kidney proximal tubule. The observation may be important for understanding the mechanisms involved in the development of diabetic nephropathy.  相似文献   
98.
本文对以次亚磷酸钠和甲醛作为还原剂对木材化学镀铜的镀液稳定性的影响做了研究。通过比较发现不同的还原剂对镀液稳定性的影响方式是不同的,还原剂与主盐的浓度比对镀液的稳定性也有较大影响,合理的配比有利于镀液的稳定,同时,还原剂与络合剂的浓度配比也是影响镀液稳定性的重要因素。通过对比两种不同还原剂的镀液中加入氯化钯的分解时间发现,以次亚磷酸钠为还原剂的镀液的稳定性远高于以甲醛为还原剂的镀液稳定性。  相似文献   
99.
The breeding system and its consequence on fruit set of Eremosparton songoricum(Litv.) Vass.,a rare shrubby legume occurring in moving or semi-fixed sand dunes of Central Asian deserts,were examined by manipulative experiments and observational studies in natural populations during the period of 2007-2009.The results showed that E.songoricum exhibits a mixed mating system.It is self-compatible,but depends strictly on pollinators to set fruits.Only two effective pollinators were detected and they triggered the specialized pollination mechanism(a 'brush type' and 'tripping mechanism').Geitonogamy becomes predominant in natural populations,because(74.5±1.3)% of visiting activity happened within or between inflorescences and(24.3±1.4)% occurred between ramets.As a result,inbreeding depression caused by geitonogamous selfing inevitably happened under natural conditions,showing 2.36 times less fruit set than was achieved by hand cross-pollination.The results explained the rarity of the species due to its breeding system,and will assist to develop suitable conservation strategies in severe desert environments.  相似文献   
100.
Lack of available workforce in motor-manual operations has led to increased interest in mechanized precommercial thinning (PCT) treatments. We evaluated 15 years of growth and yield development of a very dense (27,000 stems ha–1) balsam fir (Abies balsamea (L.) Mill) and black spruce (Picea mariana (Mill.) B.S.P.) stand after six PCT treatments: (1) motor-manual (MAN), (2) motor-manual with crop tree release (MAN-C), (3) mechanized (MEC), (4) mechanized with residual patches (MEC-P), (5) semi-mechanized (mechanized followed by motor-manual, MEC-S), and (6) unthinned control (CON). Compared to CON, both MAN and MEC-S increased height of balsam fir study trees by 53–56% and diameter at breast height (DBH) by 57–58%. MAN-C and MEC-S increased DBH of black spruce study trees by 15–31% over all other treatments. The proportion of merchantable basal area (BA) was higher in MAN (62%) and MEC-S (56%) than in CON (22%) and MEC (25%), without a reduction in total BA. PCT treatments that provided a uniform distribution of potential crop trees (MAN, MEC-S) performed better than MAN-C and MEC-P, while MEC yielded the poorest responses. Our findings highlight the need to develop new tailored mechanized systems for high wood production and low operational cost.  相似文献   
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