某大型铜矿境界优化及投达产方案研究

根据位于西藏高原地区的某大型铜矿资源情况及开采条件,采用当量品位Eq Cu来代表吨矿中4种有用元素的价值。进行了境界优化和终了境界圈定,在确定开采规模的基础上,对矿山的投产达产方案进行了比选和推荐,最终选择"分期开采,确定首采境界小规模投产,后过渡至达产规模"的方案。     

某铜钼矿山低品位矿石利用方案研究

本文以某大型铜多金属矿山为例,通过盈亏平衡品位分析,合理确定该矿的盈亏平衡品位,以及境界内低品位矿石利用的边界品位。全面评估低品位矿是否前期堆存还是后期单独处理,选取3个品位方案进行对比分析。不同方案对应的采矿排产计划不同,后期追加的采矿设备和堆场投资不同,选矿厂处理的矿石品位亦有所不同。因此,从技术与经济角度对各方案进行了详细的对比分析,为投资者决策提供依据。     

基于MineSight软件的露天钨钼矿境界优化及应用

根据矿体赋存状态及开采技术条件,某钨钼矿适合采用露天开采方式。为了得到最优开采境界,采用MineSight软件进行境界优化和分析。综合考虑技术经济参数和边坡角对露天开采的影响,得到了14个露天境界,选择净现值最大且境界增量剥采比小于经济合理剥采比的境界为最优开采境界。根据优化后的结果,对境界进行了圈定,终了境界内可采矿量共计17 977.2 kt,矿石平均品位WO_3为0.194%,Mo为0.022%;剥离废石量33 158.9 kt,平均剥采比为1.84 t/t。     

长山壕金矿东露天采场境界重新圈定及其稳定性分析

露天矿山边坡稳定性是矿山安全生产的主要影响因素之一。针对长山壕金矿东露天采场逐渐转入深部开采后出现的多处区域不同规模的滑坡及不稳定现象,对原东露天采场境界进行重新圈定,并对重新圈定的露天境界边坡进行了稳定性分析。详细介绍了东露天采场境界方案比选、道路参数的选择与设置、露天境界的重新圈定及边坡稳定性分析等。结果表明,优化后的露天境界边坡整体处于稳定状态,满足安全生产要求。     

对钨矿应用配矿数学模型的探讨

在钨矿脉开采中,矿石品位的均衡对于矿山的生产具有重要的意义。以往都用手工试凑法进行矿石品位的均衡,本文探讨利用运筹学中的线性规划建立配矿数学模型,并用电子计算机求解的方法进行矿石品位的均衡。后者可以进行多种方案的配矿,并能为矿山编制采掘计划提供必要的数据。     

紫金山低品位铜资源全面利用精细采矿技术研究

我国战略铜资源矿石品位整体相对国外矿山较低,开发利用低品位铜资源意义重大。开采利用铜矿石品位0.3～0.5%的低品位资源,由于矿石价值低,通常开采效益较差。福建紫金山铜矿地质采用7个等级品位精确圈矿、采矿采用混爆、分采、分运精准控制方法,将原边界品位的0.2%、最低工业品位0.4%的规范规定,下调至工业利用最低利用品位0.15%的新要求,做到了资源利用的最大化;高于0.25%的矿石配矿后送至选矿厂浮选,保证选矿回收率达到90%;0.15%～0.25%的铜矿石破碎后送至湿法堆场浸出,回收率可达到65%;低于0.15%的含铜废石在废石场自然堆浸回收,整体利用水平达国内外最好水平。矿山开采利用低品位矿石获大巨大经济效益。     

基于3DMine软件的露天矿山开采境界圈定

合理的露天开采境界直接关系到矿山经济效益，而境界的圈定是一项非常复杂的工作。根据某矿山的开采技术条件，利用3DMine软件建立了矿体实体模型和经济模型，并进行了露天开采境界圈定，通过不断优化，得出该矿山的最优露天开采境界。选择底标高为1 215 m的露天境界为最终的优化境界，考虑到露天坑底最小宽度及台阶坡度影响，选择1 245 m为最低平台高度。     

当量法在多金属矿储量计算中的应用

在多金属矿地质项目中,经常遇到某岩段同时含有多个矿种,每个单独矿种均达不到最低工业品位,但利用当量法折算为主要矿种后,能达到甚至大大超过最低工业品位,进而能圈为矿体,通过对圈定矿体的综合回收利用,实现其经济价值。本文主要以某铅锌铜金银多金属矿为例,详细介绍当量法的计算方式和折算规则,与经常进行储量计算工作的同事共同探讨。     

动态经济开采边界圈定方法在凡口铅锌矿低品位矿体开采中的应用

凡口铅锌矿以矿石品位高而著称，但在东区-80m水平以下出现了部分低品位铅锌矿。文中针对如何合理开采这部分铅锌矿，提出了适应市场经济条件下的动态经济开采边界圈定方法，取得了显著的效果。     

赣南离子型稀土数字矿山应用研究

随着现代经济社会的发展,中国对矿产资源的利用逐渐加大。矿山绿色有效地开采是目前矿业公司面临的主要问题之一,建立数字矿山是解决这一问题的方法之一。以赣南某试验矿块为背景,在开采前期建立的地表模型、围岩模型、高位池、集液沟等模型,洛阳铲勘探数据建立数据库、圈定矿体并建立矿体模型。最后建立块体模型计算品位分布情况,指导现场布设注液孔。证明建立的数字矿山可以很好地指导现场的施工,优化了开采工程布设,更加合理有效地选择开采方案。     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.