关于提高金刚石钻头胎体工作能力的试验研究          下载免费PDF全文

汤凤林  沈中华  段隆臣  柳少青  孙环平  Чихоткин В.Ф. 《探矿工程》2017,44(10):55-60

在地质勘探中,金刚石钻进是一种主要的方法。在金刚石钻探生产中,钻探设备、钻头、钻探工艺、钻探生产操作技术和生产管理都是非常重要的。钻探技术经济指标与钻头胎体的工作能力关系更为密切,因此成了人们关心的问题。俄罗斯Кубасов В.В.博士等在提高钻头胎体工作能力方面做了大量的工作,取得了很好的技术经济效果。本文介绍了他们在低品级金刚石的选择性破碎处理、金刚石的热处理、金刚石钻头的低温处理和胎体性能的控制技术等方面的研究内容及取得的成果。  相似文献   

内蒙古牧区矿产开发模式选择的思路探讨     

佟宝全  阿荣 《地理科学进展》2012,31(12):1693-1699

内蒙古牧区能矿资源富集, 生态环境敏感脆弱。国家“能源安全”战略要求大规模开发利用煤炭资源的地域分工与国家“生态安全”战略要求保护生态环境保护之间存在尖锐的矛盾。解决好这一矛盾, 对我国西部生态敏感区的矿产资源合理开发利用和生态环境保护具有重要意义。对生态敏感的煤炭富集区应基于区域发展的空间均衡这一视角, 选择合理的开发模式。其分析思路为:首先, 选择典型煤炭资源开发区域, 对开发空间与生态空间的空间耦合关系进行分析, 通过比较空间耦合类型, 揭示空间失衡点, 并分析空间失衡原因。其次, 构建指标体系, 构造矩阵, 对区域空间供给能力进行分区。最后, 综合空间失衡原因、空间供给能力分区以及资源开发与生态保护的需求因素, 提出区域发展的空间均衡模式与对策。  相似文献   

科尔沁沙地持续放牧和不同强度放牧后封育草场中生物结皮生物量和土壤因子的变化   总被引：7，自引：1，他引：6  

徐杰  宁远英 《中国沙漠》2010,30(4):824-830

通过对科尔沁沙地放牧后封育样地和放牧样地生物结皮生物量的研究,探讨了不同样地生物结皮生物量的变化规律及其与环境因子的相互关系。结果表明,封育样地藓类和藻类植物的生物量显著高于放牧样地;在封育样地内,轻度、中度放牧封育区显著高于重度放牧封育区（P＜0.05）。封育样地生物结皮的土壤微生物量碳、氮含量高于放牧样地,并且各样区藓结皮土壤微生物量碳、氮含量显著高于藻结皮（P＜0.05）。在封育样地内表现为轻度、中度放牧封育区土壤微生物量碳、氮含量较高,重度放牧封育区含量较低,体现出不同强度放牧封育停牧后对土壤微生物量碳、氮影响的滞后效应。藻类植物的生物量与结皮厚度、有机质含量和粉黏粒呈极显著正相关（P＜0.01）,与细沙呈显著正相关（P＜0.05）,与粗沙呈极显著负相关（P＜0.01）。藓类植物的生物量与结皮厚度、有机质含量、粉黏粒呈显著正相关（P＜0.05）,与粗沙呈负相关,但不显著。藻类植物的生物量与土壤因子之间的相关性更为密切。  相似文献   

Effects of spring–summer grazing on longitudinal dune surface in southern Gurbantunggut Desert     

Xueqin Wang  Yuanming Zhang  Jin Jiang  Weikang Yang  Hongxu Guo  Yongfeng Hu 《地理学报(英文版)》2009,19(3):299-308

Intensive grazing in spring–summer has been responsible for environmental degradation of the Gurbantunggut Desert in recent years. The coverage of plants and biological crusts, sand surface stability and physicochemical characteristics of soil on the dune surface were conducted in 2002 (winter grazing) and 2005 (spring–summer grazing). The results showed that over 80% of the total area of the dune surface was covered by well-developed biological crusts and plants in 2002, when the interdune and middle to lower part of dune slopes were stabilized and only the crest had 10–40 m wide mobile belt. Affected by spring–summer grazing in 2005, over 80% of the total cover of biological crust was destructed and the plant coverage only reached 1/5 of that in 2002, especially the ephemeral plant cover had a great change. The value of sand transport potential in 2005 only reached 1/3 of that in 2002, but the total surface activity in 2005 was 1.6 times stronger than that in 2002. Meanwhile the mobile area began to expand from the dune top to the whole dune surface following spring–summer grazing. Compared with 2002, medium sand content of the dune surface soil increased by 13.9%, while that of fine and very fine sands decreased by 7.4% and 8.0% respectively in 2005 and the soil organic matter in 2005 was only about 1/2 of that in 2002. It is obvious that the presence of snow cover and frozen soil in winter could avoid the surface structure destruction in winter, while spring–summer grazing made excessive damage to biologic crusts and ephemeral plants. Spring is the main windy season in Gurbantunggut Desert and therefore intensive activity of dune surface occurred following spring–summer grazing, which led to a great loss of fine sand and organic matter. It can be seen that grazing season have a significant influence on the sustainable development of the desert ecosystem in Northwest China. Foundation: National Basic Research Program of China, No.2009CB421303; National Natural Science Foundation of China, No.40771032; National Science Supporting Program, No.2007BAC17B03 Author: Wang Xueqin (1964–), Ph.D and Associate Professor, specialized in aeolian sand geomorphology, desertification and its control.  相似文献   

一类新型疏水缔合聚合物的合成及成胶性能     

张新 《东北石油大学学报》2013,(2):124-128,12

以甲氧基聚乙二醇丙烯酸酯(MPEGA)和甲基丙烯酸二甲氨基乙酯(DMAEMA)为均聚单体,通过乳液聚合制备一类新型疏水缔合型聚合物P(MPEGA-DMAEMA),采用FT-IR和1HNMR表征新型聚合物的化学结构;利用主剂P(MPEGA-DMAEMA)和交联剂醋酸铬形成凝胶体系,考察主剂P(MPEGA-DMAEMA)和交联剂醋酸铬的质量分数、pH值、温度、矿化度对新型聚合物凝胶体系成胶性能的影响.结果表明:当主剂P(MPEGA-DMAEMA)质量分数为1.2%、交联剂醋酸铬质量分数为0.2%、pH值为7、温度为45e时,该新型聚合物凝胶体系具有最佳的成胶强度.将新型聚合物凝胶体系应用于岩心封堵,在最佳成胶条件下,堵水率高于90%,堵油率低于40%,具有较好的选择封堵性.  相似文献   

牧压梯度下高寒杂草类草甸土壤持水能力及影响因素分析   总被引：2，自引：0，他引：2  

吴启华  毛绍娟  刘晓琴  李红琴  张法伟  李英年 《冰川冻土》2014,36(3):590-598

以祁连山南麓坡地夏季牧场高寒杂草类草甸为研究对象,进行了封育对照（CK,禁牧）、轻度放牧（LG）、中度放牧（MG）和重度放牧（HG）下土壤持水能力及影响因素的分析. 结果表明：牧压梯度下0～10 cm层土壤最大持水量和毛管持水量均在LG最大,土壤自然贮水量LG略小于HG;而在10～20 cm和20～40 cm持水量均在HG最大,说明放牧对表层土壤的持水能力影响比深层更明显. 0～10 cm层土壤容重随牧压强度增加而增大,较深层次土壤容重基本一致,表明放牧对较深层土壤容重造成的影响远小于表层. 牧压梯度下植被地上地下生物量、枯落物、地表半腐殖质随放牧强度增大而减少;0～10 cm土壤有机质含量在MG最大,CK最小,10～20 cm和20～40 cm层土壤的有机质含量CK最大,说明不同土层有机质含量对牧压梯度的响应有所不同. 土壤持水量与多种因素有关,主要受到地下生物量、有机质和容重等因素的影响,表明随放牧强度增大,践踏使土壤表面硬度增加,土壤空隙度减少,同时家畜过度采食使地面植被覆盖降低而增加土壤水分的蒸发. 这些综合作用下引起放牧地土壤持水能力降低.  相似文献   

科尔沁沙质放牧草地土壤动物多样性特征研究     

刘新民  关宏斌  刘永江  郭砺 《中国沙漠》2000,20(Z1):29-32

在科尔沁沙质放牧草地,人为的小面积实验放牧情况下,土壤动物群落结构随放牧强度的提高发生变化,主要体现在动物密度降低、群落丰富度减小。放牧强度提高时,土壤动物生物量、密度季节动态和多样性指数无明显变化规律,重度放牧下以上指标并不明显低于封育区。土壤动物优势类群对放牧扰动的响应各自不同。以相似性指数比较土壤动物对不同牧压的响应,结果为中度放牧区较接近封育区,而重牧区分异最大。  相似文献   

甘肃酒泉盆地青西油田裂缝特征及成因分析     

李军  王德发  范洪军 《现代地质》2007,21(4):691-696

甘肃酒泉盆地青西油田泥砾岩相和泥云岩相储层中发育两种裂缝系统。采用多种方法,系统研究了不同岩相区裂缝的产状特征、电性响应特征和物性特征,并重点分析了控制裂缝形成的成岩演化成因。研究结果表明:泥砾岩相中发育有砾缘缝、粒内溶蚀缝和构造裂缝;泥云岩相中发育层面溶蚀缝、泄水裂缝及构造裂缝。裂缝系统不但对储层渗流能力有较大程度的改善,而且也具有一定程度的储集能力。母岩矿物的选择性（差异）溶蚀是控制本区裂缝和次生孔隙发育的主要因素：泥砾岩成分复杂,各种碎屑物及胶结物之间的交代、溶蚀以及不稳定碎屑颗粒的选择性（差异）溶蚀是砾缘缝、成岩溶蚀缝及大量次生孔隙在泥砾岩储层中形成的主要原因;泥云岩中存在的二元和三元纹层结构从根本上决定了裂缝的发育程度,碳酸钙的白云岩化和沸石化是层面溶蚀缝形成的主要成岩作用。  相似文献   

Low densities of sea urchins influence the structure of algal assemblages in the western Mediterranean     

Cruz Palacín  Gonzalo Giribet  Susanna Carner  Luis Dantart  Xavier Turon 《Journal of Sea Research》1998,39(3-4)

Numerous studies of interactions between urchins and algae in temperate areas have shown an important structuring effect of sea urchin populations. These studies focused almost wholly on the effect of high urchin densities on laminarian forests. In contrast, algal communities below 5–6 m depth in the northwestern Mediterranean are characterised by low sea urchin densities (<5 ind m⁻²) and the absence of laminarian forests. No previous research has addressed sea urchin/algal interactions in this type of community. To determine the effect of the most abundant echinoid species, Paracentrotus lividus, on well-established algal communities in this area, we performed a removal–reintroduction experiment in rocky patches located between 13 and 16 m depth in the northwestern Mediterranean, where sea urchin densities ranged between 0.9 and 3.4 ind m⁻². After 6 months, the cover of non-crustose algae was significantly higher in the plots from which sea urchins had been removed than in control plots (84 vs 67% cover). These removal plots reverted to their original state upon reintroduction of sea urchins. The non-crustose algae consisted of turfing and frondose forms, with the former representing some 70% of the non-crustose algal cover. Change in the cover of turfing algae was responsible for the significant increase in algal development in the sea urchin removal plots. The response of frondose algae to the treatment varied between algal species. It is concluded that grazing by P. lividus exerts a significant effect on habitat structure, even in communities with low sea urchin densities, such as those found in vast areas of the Mediterranean sublittoral.  相似文献   

刚毛藻(Cladophora)生态学研究进展   总被引：1，自引：0，他引：1  

刘霞  陈宇炜 《湖泊科学》2018,30(4):881-896

刚毛藻(Cladophora)在全球海洋及淡水中普遍存在,它为沿岸带微生物和无脊椎动物提供了生产力和微生存空间.随着水体富营养化程度的加剧,刚毛藻在沿岸带出现暴发现象,造成严重的环境污染,同时刚毛藻的存在也影响了湖泊生态修复过程中沉水植被的恢复.本文从刚毛藻形态与种类鉴定、生长与分布影响因素、生长周期与种群动态、种间关系及生物去除等研究前沿方面进行综述,并对相关研究领域进行展望,为进一步研究刚毛藻生态生理特征、有效控制和去除提供科学依据.  相似文献