半乳甘露聚糖植物胶在选矿上的应用

半乳甘露聚糖类植物胶,以田菁胶、瓜尔胶为主。本文对于植物胶的生产工艺和技术指标进行简要介绍,对于植物胶在选矿中作为硅酸盐类矿泥的抑制剂和絮凝剂进行了详细说明。国内外已在钾矿、镍矿、铜矿、金矿等选矿中应用,取得成功。     

Crenotherapy in sports medicine: the state of the art

The existing relationship linking thermal and sport medicine has developed with time. This is shown by the established beneficial effects of thermal treatments (mineral waters, mud baths, balneotherapy, aerosol applications) in a wide range of sport and non-sport related injuries. The muscle fatigue syndrome is a condition particularly worrisome for sports practising individuals. This condition impairs the cardiovascular system, as well as hematologic, renal and gastrointestinal functions, acting via biochemical and metabolic modifications of the organism, which have effects also on the psyche of the subject. The treatment of this syndrome includes the use of specific mineral waters, which underscores that the correct hydration of the organisms is a precondition to achieve high performance levels. Traumas involving muscles and skeletal segments, and precocious arthrosis occur with higher frequency in sportsmen after continuous and intense stresses. Within the scope of rheumatology, mud-baths and balneotherapy have curative and rehabilitative potentials leading to a reduction, and often a disappearance, of pain with a faster recovery of the locomotory system. The gastrointestinal system is a target of psychic as well as physical stresses displaying symptoms or diseases which may be favourably addressed with the aid of mineral waters. This treatment has proved effective in secretory and motility dysfunctions of the biliary tree allowing a rapid functional recovery. Mineral water treatments are successfully employed in the treatment of urologic disturbance and ORL and dermatological pathologies, where local applications such as mud baths, balneotherapy, showers and aerosols, play a critical role.     

低浓度拜耳赤泥充填材料制备及水化机理

针对矿山充填中拜耳法赤泥利用率较低或低浓度赤泥充填材料存在强度低、泌水量高、易收缩等问题,研究粉煤灰添加比例、脱硫石膏、石灰及激发剂对赤泥充填材料早期强度及体积稳定性的影响,采用扫描电子显微镜-能谱仪（SEM-EDS）和X射线衍射（XRD）分析手段探讨赤泥基充填材料的水化机理。结果表明,脱硫石膏促进钙矾石的生成,石灰促进粉煤灰火山灰效应,激发剂可以加快赤泥?粉煤灰水化反应进程,三者协同作用提高赤泥充填体强度。充填材料28 d抗压强度3.35 MPa,且初始及60 min流动度在200 mm以上。微观实验表明,硬化体水化产物为钙矾石、硬柱石、硅铝酸盐凝胶类矿物,水化产物通过填充孔隙,提高浆体强度。赤泥基充填材料固体废弃物利用率达到92%,无泌水,无沉缩,具有较高的经济价值和环保价值。      

分级重选—磁选—反浮选联合工艺处理某高泥赤铁矿

湖北某低品位高泥赤铁矿资源含Fe 21.24％,该铁矿原矿脉石矿物成分复杂,含有大量的易泥化的绿泥石、高岭土黏土类矿物,且目的矿物与脉石矿物呈现微细粒交代嵌生结构,不利于铁精矿品位的提高.结合工艺矿物学研究及不同工艺方案对比试验结果确定了筛分分级—棒磨粗磨—溜槽重选—高梯度磁选—磁选精矿再磨—反浮选的联合工艺流程,该工...     

矿物材料在有机废水处理中的应用

天然或改性矿物材料对有机污染物具有良好吸附作用,将其用于有机废水的处理是目前污水处理研究的热点.本文对其在有机废水处理中的应用现状进行了综述,并对其应用前景进行展望.     

矿泥对氰化浸出影响的试验研究

矿泥中的粘土矿物易絮凝成网状多孔结构物，能够吸附已溶金，影响金的氰化浸出。为控制矿泥影响，含泥物料可在高碱、高氰条件下进行两浸两洗；从物料中将矿泥分出，进行炭浸，可显著提高金浸出率。     

全尾砂无耙深锥稳态浓密性能分析

结合沉降和压滤实验, 对脱水性能数据进行曲线拟合获得连续网状结构形成浓度、压缩屈服应力和干涉沉降系数, 引入Usher提出的稳态浓密性能预测算法, 建立了无耙深锥浓密模型, 分析了絮凝剂单耗、底流中固相的体积分数、泥层高度等对固体通量和固体处理能力的影响规律.研究结果表明: 絮凝剂添加量对沉降区域影响大于压密区域, 20 g·t-1时浓密性能较好, 底流中固相的体积分数越大固体通量越小; 在沉降区域, 固体通量仅与浓度有关, 不受泥层高度影响; 在压密区域, 固体通量为浓度与泥层高度的方程; 模型参数范围内, 当泥层高度 < 3.5 m时, 固体处理能力为浓度与泥层高度的方程, 当泥层高度>3.5 m时, 固体处理能力与固体通量随底流中固相的体积分数变化规律一致.      

硼泥掺杂对磷酸镁水泥性能的影响

硼泥是硼砂和硼酸生产过程中产生的工业废渣,大量排放不但占用大量的土地,造成地下水污染,失水后飞散成为粉尘,还造成大气污染。将硼泥掺杂到以重烧氧化镁和磷酸二氢钾为原材料制备的磷酸镁水泥中,研究硼泥掺杂对磷酸镁水泥性能的影响。结果表明：硼泥能够延长磷酸镁水泥的缓凝时间,同时能够提高水泥的抗压强度。硼泥的最佳掺量为10%,水泥凝结时间由原来的29 min延长到35 min,水泥抗压强度由56.21 MPa提高到58.7 MPa。XRD分析结果表明,硼泥的加入没有改变磷酸镁水泥的矿相结构。本研究可以为硼泥固废资源化利用提供依据。     

强磁选-重选联合工艺回收尾矿、尾渣中铁的研究

采用SLon立环脉动高梯度磁选机强磁选和离心机重选联合工艺,可有效回收选矿尾矿、赤泥、浸金尾渣和焙烧中矿的铁资源.研究表明,SLon立环脉动高梯度磁选机在背景场强为0.7~0.9 T时强磁粗选抛尾;再对粗选精矿采用离心机在转速为400 r/min,洗涤水为2400~2600 mL/min进行精选,可以得到TFe品位60%以上的铁精矿,且有较高的精矿回收率.     

RNA-binding proteins tamed

OBJECTIVES: Enhancement of the remineralisation of artificial enamel lesions has been observed in an intraoral model whether subjects chewed gum sweetened with a non-cariogenic sweetener such as sorbitol [1-3] or sucrose [4] after meals or snacks, and with use of a conventional (1500 ppm F) fluoride dentifrice. Since most of the clinical surveys which have shown the potential cariogenicity of sucrose chewing gum [5] were conducted before use of fluoridated dentifrices became widespread, the effect of fluoride dentifrice on de- and remineralisation of artificial lesions in enamel in response to chewing sucrose-sweetened gum has been examined with the aim of attempting to resolve this apparent discrepancy. METHODS: Subjects wore an intraoral device bearing an enamel lesion and chewed one piece of sucrose gum for 20 min after each of three meals and two snacks daily for two 3-week periods, during which they used a dentifrice containing either 0 or 1500 ppm F in a double-blind, cross-over design. Measurement of the mineral content of the lesions was determined by microradiography or polarised light microscopy. RESULTS: It was found that remineralisation tended to occur with 1500 ppm F dentifrice, but demineralisation with non-F dentifrice; the difference in enamel mineral content between the two periods was significant (P < 0.05). CONCLUSIONS: The results indicate that the potential cariogenicity of sucrose-containing chewing gum may indeed be negated by the use of a conventional fluoride dentifrice.     

Effect of the different factors on the iontophoretic delivery of calcium ions from bentonite

The calcium content of mud patches used for therapy is very small. Several mineral clays originating from Hungary served as a base material for experiments in order to find a suitable drug for transdermal introduction of calcium ions into the body. The Ca++ transport through the pig skin has been investigated in vitro in diffusion cells applying iontophoresis. Studies of electrical and physicochemical factors acting on the permeation kinetics of in vitro experiments were performed. The utilization of direct current has intensified the Ca++ transport through the pig skin (129.78+/-26. 15 microgram Ca/cm2). On using pulsate currents the amount of the Ca++ penetrating through the skin was 5-10 times higher (283.18+/-16.89 microgram Ca/cm2, 388.71+/-19.90 microgram Ca/cm2) than that of the passive transport (36.22+/-14.20 microgram Ca/cm2). The amount of Ca++ cumulated in the receptor compartment was directly proportional to the amount of bentonite (a natural mineral clay with a large cation exchange capacity) in the donor compartment and to the concentration of Ca++ in the lattice of the applied mineral clay. Therefore, the experiments were carried out on a bentonite previously enriched in Ca++ in its lattice (50 mg Ca/g bentonite). The results of the in vitro studies could open a new field of application in the therapy of osteoporosis or in the use of mineral substances.     

Some devices for computed tomography radiotherapy treatment planning

Some simple technical devices for radiotherapy planning using computed tomography are reported, including (a) a wide, flat-topped plywood couch, (b) a poultice patch to mark the treatment area, (c) a Plexiglas scan level marker, and (d) reference anteroposterior radiographs using a conventional X-ray TV system.     

云南文山铝业赤泥资源化利用方案设想

根据铝土矿原矿成分、氧化铝生产工艺和云南省的产业发展规划,提出了文山铝业拜耳法赤泥资源化利用的一种处理方案。赤泥通过选矿工艺的优化,选出铁、钛混合精矿,经电炉熔炼生产高钛渣,为钛白粉生产提供原料。尾渣通过选矿降低了铁和碱的含量后,可以大幅拓宽赤泥在建材中的应用途径,提高用量。     

矿物材料在重金属废水处理中的应用

天然矿物材料对重金属离子具有吸附作用、离子交换作用和化学活性作用，可广泛用于重金属废水处理。本文对其在重金属离子废水处理中的应用现状进行了综述。并对其应用前景进行展望．     

Management of Fluid Mud in Estuaries, Bays, and Lakes. II: Measurement, Modeling, and Management

Techniques for measurement, modeling, and management of fluid mud are available, but research is needed to improve them. Fluid mud can be difficult to detect, measure, or sample, which has led to new instruments and new ways of using existing instruments. Multifrequency acoustic fathometers sense neither density nor viscosity and are, therefore, unreliable in measuring fluid mud. Nuclear density probes, towed sleds, seismic, and drop probes equipped with density meters offer the potential for accurate measurements. Numerical modeling of fluid mud requires solving governing equations for flow velocity, density, pressure, salinity, water surface, plus sediment submodels. A number of such models exist in one-, two-, and three-dimensional form, but they rely on empirical relationships that require substantial site-specific validation to observations. Management of fluid mud techniques can be classified as those that accomplish: Source control, formation control, and removal. Nautical depth, a fourth category, defines the channel bottom as a specific fluid mud density or alternative parameter as safe for navigation. Source control includes watershed management measures to keep fine sediment out of waterways and in-water measures such as structures and traps. Formation control methods include streamlined channels and structures plus other measures to reduce flocculation and structures that train currents. Removal methods include the traditional dredging and transport of dredged material plus agitation that contributes to formation control and/or nautical depth. Conditioning of fluid mud by dredging and aerating offers the possibility of improved navigability. Two examples—the Atchafalaya Bar Channel and Savannah Harbor—illustrate the use of measurements and management of fluid mud.     

Water supplementation enhances the effect of high-fiber diet on stool frequency and laxative consumption in adult patients with functional constipation

BACKGROUND/AIMS: The purpose of this study was to determine the effects of a high-fiber diet and fluid supplementation in patients with functional chronic constipation. METHODOLOGY: One hundred and seventeen patients with chronic functional constipation (aged 18-50 years) were randomly divided into two treatment groups. For two months both groups consumed a standard diet providing approximately 25 g fiber per day. Group 1 (58 patients) was allowed ad libitum fluid intake, while Group 2 was instructed to drink 2 liters of mineral water per day. Compliance was monitored throughout the study and results were assessed in terms of bowel-movement frequency and laxative use. RESULTS: Fiber intake was similar in the two groups, while total daily fluid intake in Group 2 (mean 2.1 liters) was significantly greater than that of Group 1 (1.1 liters)(p < 0.001). In both groups, there were statistically significant increases in stool frequency and decreases in laxative use during the two-month trial, but both changes were greater in Group 2 (stool frequency: p < 0.001 vs. Group 1; laxative use: p < 0.001 vs Group 1). CONCLUSIONS: A daily fiber intake of 25 g can increase stool frequency in patients with chronic functional constipation, and this effect can be significantly enhanced by increasing fluid intake to 1.5-2.0 liters/day.     

Using iron-rich red mud from alumina production at steel plants

In the low temperate sintering of bauxite with alkali, the magnetic properties of red mud change on account of the formation of a new mineral—maghemite. By this means, waste production may be reduced by a factor of 1.5. The concentrates obtained are suitable for use in ferrous and nonferrous metallurgy and in rare-earth production. This technology provides environmental benefits and expands the range of raw materials for steel production.     

The influence of low frequency acupuncture on a demand pacemaker

Various complications with demand pacemakers have been known to originate from their own sensing mechanisms. In these complications, electromagnetic interference is one of the well known causes of oversensing with demand pacemakers. The influence of low frequency acupuncture as a specific type of electromagnetic interference on a demand pacemaker was examined during a cervical operation. It was found that low frequency acupuncture is a cause of electromagnetic interference with demand pacemakers. Therefore, caution should be exercised when using the low frequency acupuncture on a pacemaker patient.     

Comparability and discriminating power of 4 plaque quantifications

This study was designed for analysis of the discriminating power of 4 different quantifications of supragingival plaque: (1) plaque wet weight (PWW); (2) the plaque index (PlI); (3) the PLQ index measuring the coronal extension of plaque; (4) the area % of stained plaque. Different quantities of plaque were produced by adding chlorhexidine acetate (CHX), hydrogen peroxide (H2O2), or sucrose to experimental chewing gums. Total mean scores of 12 subjects in each of 3 test groups revealed that chewing of CHX gum resulted in the lowest plaque scores with all 4 quantifications and that the highest scores were recorded for the PWW or PlI of the sucrose gum users. Chewing of the H2O2 gum produced as much plaque as the sucrose gum when evaluated according to the PLQ index and exceeded the sucrose gum scores when evaluated according to the area % index. The PWW discriminated best between low, medium and high plaque scores after chewing of both CHX, H2O2 and sucrose gums. PlI scores 1 and 3 remained stable whereas the frequency of PlI score 0 strongly decreased and that of score 2 strongly increased when going from gums producing low (CHX) and medium (H2O2) to large (sucrose) amounts of plaque. The PLQ index discriminated well between low and medium but poorly between medium and large amounts of plaque. The area % index functioned well when subjects with low (CHX) and medium (H2O2) plaque scores were subgrouped into those with < 30%, 30-70% or > 70% of their tooth surfaces covered with stained plaque.(ABSTRACT TRUNCATED AT 250 WORDS)     

UTILIZATION OF ALUMINA RED MUD FOR SYNTHESIS OF INORGANIC POLYMERIC MATERIALS

Red mud is a residue coming from the metallurgical treatment of bauxite with the Bayer process. Million of tons of red mud are produced annually worldwide and disposed of on land, degrading vast areas. Therefore, red mud utilization is a first-priority issue for any alumina plant. In the present work, the potential use of red mud for synthesis of inorganic polymeric materials through geopolymerization process was studied. The main focus was the production of inorganic polymeric materials that could be used in the construction sector as artificial structural elements such as massive bricks. The geopolymerization process involves a chemical reaction between red mud and alkali metal silicate solution under highly alkaline conditions. The product of this reaction is an amorphous to semi-crystalline polymeric structure, which binds the individual particles of red mud transforming the initial granular material to a compact and strong one. The effect of main synthesis parameters—like solid-to-liquid ratio, caustic soda as well as soluble silica concentrations, and metakaolin addition—on the properties of red mud-based inorganic polymeric materials was investigated. The results showed that the produced materials have high compressive strength, very low water absorption, satisfactory apparent density, and excellent fire resistance. Therefore, this work proved that the red mud-based inorganic polymeric materials have promising properties and have the potential to be used as artificial structural elements in the construction sector.