耙料机纠偏原理及严重偏斜的应对措施

通过分析耙料机发生严重偏斜的原因和处理措施,从耙料机的结构入手,讨论耙料机在工作时的纠偏原理和过程,提出解决耙料机严重偏斜问题的措施.     

耙料机电气控制系统改造及效果分析

介绍耙料机电气控制系统的改造情况及新技术应用。通过改造,消除了耙料机系统存在的隐患,延长了耙料机使用周期,提高了耙料机正常运行的可靠性。     

PL380/52特大型散料门式耙料机的设计

PL380/52特大型散料门式耙料机是大型化肥生产装置的重要配套设备。详细论述特大型散料门式耙料机设计的目的、依据和方法,为设计更大耙料能力和更大跨度的散料门式耙料机提供参考。     

门式耙料机维护方式探讨

PL240／48型门式耙料机的主要任务是将尿素散装库内的尿素连续耙取至皮带输送机上。当耙料机跨过料区行走时，通过装有回转耙链和耙板的耙臂上下摆动，耙板切入料堆之中，利用耙链的连续牵引，耙板把尿素不断耙取至安装于料堆一侧的皮带输送机上，将尿素从尿素散装库中运出。PL240／48型门式耙料机主要由机械传动、     

变频器、PLC在门式耙料机上的应用

门式耙料机电气控制复杂,工作环境恶劣,故障频繁,将PLC与变频技术相结合,对门式耙料机进行改造,减少了设备,简化外部接线,新增部分功能,完全能满足工艺操作的需要.     

门式耙料机的行走与走偏

介绍了耙料机的行走及防偏装置，分析耙料机在行走方面的有关故障，并提出了相应的措施。     

PLC计算机新技术在耙料机上的应用

内蒙古化肥厂耙料机是整个包装系统的龙头,由于散装库的高温、腐蚀和粉尘等恶劣工作环境,使工作可靠性下降,故障频繁,因而对耙料机电控进行改造,采用PLC控制,可确保耙料机稳定长周期运行。1　硬件部分的设置耙料机PLC控制系统可采用OMRON公司C200H系列可编程序控制器,该PLC机具有可靠性高,抗干扰能力强,运行稳定等特点。PLC电控系统框图为:　　a.PLC基本配置CPU主机C200H-CPU-111块8K存储器C200H-MRS311块16路输入单元1A2228块16路输出单元OC2252块8路输出单元OC2241块通讯单元O200H-LK202块b.上位机基本配置386工业控制…     

尿素耙料机主、副耙板碰撞原因分析及调整

介绍尿素耙料机主、副耙板碰撞情况,分析原因,通过调整副耙臂双向电动卷扬机钢丝绳,问题得以解决,使耙料机稳定运行。     

浅谈PLl00／30型门式耙料机的维护

PLl00／30型门式耙料机的日常维修和保养,容易发生的故障以及处理方法。对耙料机的改进也作了阐述。     

可编程序控制器在耙料机上的应用

可编程序控制器在耙料机上的应用储群杰（金陵石化公司化肥厂，江苏南京，２１００３３）金陵石化公司化肥厂耙料机是整个包装系统的龙头，由于散装库的高温、腐蚀和粉尘等恶劣工作环境，使工作可靠性下降，故障频繁，因而对耙料机电控采用ＰＬＣ进行了改造。１硬件部分耙...     

犁钉型螺杆组合方式对PVC材料形态和性能的影响

通过对组合式注塑螺杆均化段物料流动建立理论模型并结合实验验证，分析探讨了注塑螺杆构型对PVC塑化效果的影响，研究表明：犁钉式螺杆注塑PVC制品的性能明显优于普通注塑螺杆成型PVC制品的性能；犁钉的安装形式和安装位置对注塑制品的性能有很大的影响，犁钉螺纹元件前置比后置能获得更好的效果。     

介绍一种新颖的纺丝螺杆——犁钉分流混合型螺杆

本文介绍了北京服装学院机电系螺杆课题组,为改进圆销钉螺杆在熔体塑化及混合等方面的不足,经研究精心设计了犁钉分流混合型螺杆。该螺杆可使熔融体达到三维混合,提高了熔体均匀性等优点。     

纤维素醚生产工艺和设备改进

介绍了最近十年纤维素醚生产工艺及设备的改进工作,分析了捏合机与犁刀反应器在纤维素醚生产工艺中的不同特点。伴随着纤维素醚产业的快速发展,单套装置的生产能力正在从几百吨级向几千吨级过渡,新型装备代替老式装备是一种必然趋势。     

芦苇人工湿地造纸废水资源化利用

在地势低洼平坦的盐碱地，用造纸工业废水创造湿地环境种植芦苇，利用人工芦苇湿地处理造纸废水，处理后的废水回流再利用，芦苇湿地生产的芦苇用作造纸原料。芦苇湿地经过3～4年的改良又可开垦为耕地，实现造纸废水资源化利用，经济效益、生态效益、社会效益显著。     

Effect of radiation on the friction-wear properties of polyetherketone with a cardo group

We studied the effect of radiation on the friction-wear properties of polyetherketone with a cardo group (PEK-C) with a MM-200 model friction and wear tester. We found that radiation could improve the friction-wear properties of PEK-C to a certain degree. The friction coefficient and wear rate of PEK-C decreased as the radiation dose increased from 5 × 10⁴ to 1 × 10⁷ Gy. Scanning electron microscopy results revealed that the size of wear debris of unirradiated PEK-C was larger than that of irradiated PEK-C. The worn surface of unirradiated PEK-C showed plough marks, whereas the worn surface of irradiated PEK-C did not show plough marks; its surface was quite smooth. With the frictional couple of a carbon steel ring and an irradiated PEK-C block, a relatively uniform and coherent transfer film was formed on the ring surface. It was inferred that the transfer film contributed largely to the decreased friction coefficient and wear rate of the irradiated PEK-C. An IR spectrum showed that no significant chemical change took place when the PEK-C sample was irradiated. Thermal analysis results showed that radiation changed the thermal properties of PEK-C, therefore, its friction-wear properties changed at the same time. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 962–967, 2001     

犁钉螺杆在VC403上纺制PP长丝的应用

在VC403纺丝机上应用犁钉螺杆生产PP长丝。生产实践表明:犁钉螺杆以分流三维混合为特征,加大了槽深,强化了剪切、混合。与常规螺杆相比,生产过程稳定,工艺易于控制,产品物理性能指标提高,不匀率降低,相同工艺条件下,产量约增加30%;同样产量下,螺杆转速、加热温度降低,减少了能耗。     

共轭环翅填料的流体力学与传质性能

以正犁削金属表面翅成形技术加工出共轭环翅填料,用富氧水解吸方法测定了38 mm铝材共轭环翅填料的流体力学和传质性能,并在相同喷淋密度和气速条件下,与同尺寸光滑表面的共轭环填料进行比较。结果表示,共轭环翅填料的单位填料高度压降比普通共轭环填料平均增加15.2%,而传质单元高度则平均降低18.3%;在中等喷淋密度60 m3/(m2.h)以下,共轭环翅填料具有较好的综合性能。     

河西走廊灌漠土钾素状况及施钾效应

多点调查表明 ,河西灌漠土全钾、速效钾比 70年代末平均降低了 2 2 %和 4 1.2 % ,耕层全钾、缓效钾、速效钾平均含量分别为 1.4 2 %、10 34mg/kg和 14 2 mg/kg。带田作物及小麦、玉米、甜菜、马铃薯单作 ,当季施钾均无明显增产效应。当土壤速效钾为 70 mg/kg以下时 ,春小麦、玉米、施钾显效 ;缓效钾为 70 0 mg/kg以下、速效钾 12 0mg/kg以下时 ,带田作物施钾显效。     

Effects of Some Soil Management Systems on Soil Physical Properties,Microbial Biomass and Nutrient Distribution Under Rainfed Maize Production in a Humid Rainforest Alfisol

The inter ac tion of land use and sea sonal mi cro cli mat ic events could explain the dif fer ences in soil qual ity char ac ter is tics which medi ate bio log i cal and phys i cal pro cesses of the soil under low input land use sys tems (plough plus har row, strip/heap till age, man ual clear ing/no till). It is hy poth es ised that in a humid trop i cal Alf isol, low input sys tem involv ing reduced till age meth ods, and min eral fer til izer and/or live stock manure use, would sup port a higher den sity of micro bial bio mass, soil aggre ga tion, organic C and total N and hence improve ment in soil qual ity. The dynam ics of biotic and abi otic soil prop er ties as affected by meth ods of seed bed prep a ra tion char ac ter ised by man ur al input and mi cro cli mat ic tran si tions from wet to dry sea son was stud ied in a maize field in a trop i cal rain for est Alf isol in Ak ure, a humid rain for est zone of Nige ria. Each year, tri als were car ried out dur ing the rainy (April–July) and late (September–December) sea sons of 2001 and 2002. Meth ods of seed bed prep a ra tion involv ing plough plus har row, strip/heap till age and no till age, and addi tion of dif fer ent gra di ents of manures (mineral N and/or plant debris and live stock litter) were imposed on the soil at the site of the exper i ment (of com pa ra ble phys i cal prop er ties of bulk den sity and texture). Among the treat ments, there were sig nif i cant dif fer ences in the val ues of water hold ing capac ity, aggre gate sta bil ity (macro-aggre ga tion), con cen tra tions of micro bial bio mass, organic C, total and min eral N and CEC. In the rainy and late sea son tri als, the strip/heap till age and the no till treat ments improved aggre gate sta bil ity (as mea sured by the per cent ages of aggre gates between 2 and 10 mm of soil) and water hold ing capac ity over plough + har row. For exam ple, in the rainy sea son trial, under treat ments involv ing strip/heap till age and the no till alone and in com bi na tion with live stock manur ing and res i due reten tion, the val ues of aggre gates between 2 and 10 mm range from (110–116; 113–119 g/kg) and water hold ing capac ity (0.11–0.14; 0.12–0.15 g/g) over plough + har row (107.3 g/kg; 0.11 g/g). Sim i lar trends were found in the val ues of soil micro bial bio mass C (377, 353; 547, 490 μg/g dry soil), soil organic C (3.8, 4.3; 5.2,5.5 g/g) and total N (2.9, 2.3; 2.9, 3.0 mg/g) for strip/heap and no till treat ments com pared to plough + har row (327.6 μg/g dry soil; 3.4 g/g; 2.8 mg/g). Although the %C micro bial to C organic ratio (an indicator of the utilisation of organic carbon by the microbes in terms of organic matter turn over rate) was sta ble for all treatments, its magnitude was not con stant but increased with increases in soil C concentration. The values of microbial bio mass carbon to organic carbon (Cmic: Corg) ratio were higher under plough ing and heap till age com bined with min eral N (0.096, 0.099) than in no-till treat ment (0.083) in the rainy sea son trial. Similar trends were obtained in the magnitudes of this param eter in the late sea son trial. Microbial bio mass correlated positively with both soil organic C (y = 0.393c − 6.7; r² = 0.99; P< 0.05) and water hold ing capacity (y = 0.87c^0.39; r² = 0.94; P<0.05) and neg a tively with bulk density (y=−0.3c+1.9; r² = 0.90; P<0.05), strong positive lin ear cor re la tion were also found between soil macro aggre gates and other soil prop er ties: micro bial bio mass C (y=0.41c−18.4; r²=0.95; P<0.05), organic C (y=0.61c−14.3; r² = 0.97; P<0.05) and total N (y = 0.063c−10.8; r² = 0.98; P<0.05). Huge responses of soil characteristics were obtained from low input land use systems (plough plus har row, strip/heap till age, manual clear ing/no till). These proper ties mediate many biological and physical processes of soil carbon, N mineralisation, soil aggregation and water hold ing capacity and microbial bio mass, and led to improvement in soil quality. The emerged trend was that the interaction of land use, clay content of the soil and seasonal micro climatic events could explain the heteroge neity of soil components among treatments.     

Catalytic growth of carbon nanotubes on stainless steel: Characterization and frictional properties

Carbon nanotubes (CNTs) have been grown both on a sample of stainless steel (317-2R) and on the same steel coated with cobalt colloid nanoparticles. Both materials are suitable supports for the growth of vertically aligned carbon nanotubes, although a more sparse growth of significantly thicker carbon nanotubes is observed in the case of the bare steel. We find that carbon nanotubes grown directly on the stainless steel support show very poor tribological behaviour whereas the support using nanoparticles for carbon nanotube growth displayed interesting tribological properties with friction coefficients of approximately 0.1–0.2. The modified CNT material (studied by Raman spectroscopy) adheres to both mating surfaces avoiding direct contact between asperities and plough so the friction and wear processes decrease greatly.