我国钾盐产业及市场需求运行情况

从我国的钾盐产业政策,钾资源,钾盐的科研、生产,近年的钾盐产量、消耗量与剩余结转库存量,总结我国钾盐产业运行情况。指出我国正合理引导开发利用钾盐资源;2009年不用进口钾盐即可满足国内需求;中远期我国钾盐对外依存度应降到30％;构建我国钾肥的稳定供应体系,打破垄断格局。     

2017年全球钾盐资源及产销状况变化

介绍2017年全球钾盐资源储量及资源性钾盐产品的生产情况;全球钾盐消费缓慢增长,贸易量增幅较大。分析全球钾盐产品供需形势及我国在钾盐供应方面存在的问题,并提出政策建议,即在保证国内钾盐基本产能的基础上,减少国内钾盐产量,增加进口量;获得海外生产份额;鼓励用进口氯化钾加工硫酸钾。     

2004～2005年世界钾盐、磷肥、硫消费与需求

由于世界钾盐市场需求旺盛，钾盐增长势头强劲，2004年世界钾盐已连续两年交货量超过产量，致使年底钾盐生产企业的库存量均有所下降。     

1998年世界钾盐工业简评

目前全球约有１３个钾盐生产国,大多数通过地下开采回收钾盐。主要的７个钾盐生产国中,加拿大、白俄罗斯、俄罗斯的钾盐储量最大,１９９８年这３个国家的钾盐总产量约占全球钾盐总产量（２５５０万ｔ）的６３％;其次德国的钾盐产量占１４％、以色列占７％、约旦占４％,其余的来自包括美国在内的另外７个国家。全球消费钾盐的国家约有１５０多个。美国是最大的钾盐消费国,约占全球钾盐消费总量的１／４;中国是第二大钾盐消费国,约占全球消费总量的１２％;巴西是第三大钾盐消费国,约占全球消费总量的１０％。化肥仍然是钾盐的主要消…     

拉美地区钾盐资源的分布及成矿规律分析

全球钾盐资源储量丰富但分布极不均衡,绝大部分钾盐资源集中在加拿大、俄罗斯等国。拉美地区已发现钾盐资源,多数为含钾卤水,少部分为地下固体钾盐,发现拥有钾盐资源的国家有巴西、阿根廷、玻利维亚、智利和秘鲁等国。通过对拉美地区钾盐资源分布及开发利用现状进行分析,总结了中国企业开展境外钾盐开发合作中的困境,并对拉美各国开展钾盐矿产资源勘查开发的可进入性及优先进入目的国进行了评价与讨论,这为中国地勘单位和企业到拉美进行钾盐勘查、开发投资提供科学指导。     

1999年欧洲钾盐产量减少

1999年欧洲许多钾盐生产企业的产量均有所下降 ,致使欧洲钾盐的总产量由上一年的 51 0万ｔ下降到 4 90万ｔ。由于洪灾 ,英国Ｃｌｅｖｅｌａｎｄ钾盐公司的钾盐产量减少 ;法国Ｍｉｎｅｓｄｅｐｏｔａｓｓｅｄ′Ａｌｓａｃｅ钾盐公司关闭了部分矿山。新千年之初 ,德国ＫａｌｉｕｎｄＳａｌｚ公司暂时停止了钾盐生产。只有西班牙Ｉｂｅｒｐｏｔａｓｈ钾盐公司的产量有增长。1999年欧洲钾盐产量减少     

我国钾盐供应风险分析

2016年世界钾盐探明总储量比2015年增长10. 42%,但2016年钾盐产量减少,大生产商存在限产保价现象。我国钾盐资源储量的保证程度比较低,钾盐基础储量可保证59年,经济可采储量只能保证8年,钾肥长期依赖进口满足需求。进入21世纪以来,钾盐进口价格快速上涨,我国钾盐供应风险有增大趋势。针对我国钾盐供应中存在的问题,提出了相应的政策建议。     

中国钾盐工业欲破资源坚冰

目前,中国钾盐对外依存度高达70％,钾盐企业正在积极寻找矿源、加大非水溶性钾资源以及海水提钾的技术开发力度,以应对全球钾盐价格暴涨的局面。中国是世界上最大的钾盐消费国和进口国,钾盐产品年消费量已达1100余万t（以氯化钾实物计）,年进口量超过700万t。随着中国钾盐工业发展迅速,资源短缺的矛盾更显突出。     

可溶性钾盐矿加工工艺实践

本文较全面地阐述了目前可溶性钾盐矿加工工艺方法,并对世界主要生产企业钾盐的加工实践展开深入剖析,为钾盐生产企业、设计研究单位了解并掌握钾盐加工技术提供可靠参考依据。     

世界钾盐生产贸易现状

详细介绍了当前钾盐生产贸易形势,以及钾盐采矿方法.为我国钾盐"走出去"去国外寻找资源提供了参考.     

Confocal microscope—A valuable tool for examining wood-coating interface

The suitability of confocal laser scanning microscopy (CLSM) in examining a wood-coating interface was evaluated using a clear coating system. A comparison of the images of the wood-clear coating interface obtained using CLSM and light microscopy (LM) showed a marked superiority of CLSM in revealing the details of the physical nature of the interaction between the clear coating and the wood cell walls in the surface layer. The most distinct advantage of CLSM was in its ability to clearly resolve penetration of the coating into very fine cracks in cell walls, details not obtainable with LM. The information presented here demonstrates that CLSM has the potential to greatly enhance our understanding of the physical aspects of an interaction between the wood and coating at the interface.     

Failure of tannic acid to inhibit digestion or reduce digestibility of plant protein in gut fluids of insect herbivores

The rate of hydrolysis of the abundant foliar protein, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPC), in enzymatically active gut fluid ofManduca sexta larvae is very rapid and is unaffected by the presence of tannic acid, even when tannic acid is present in the incubation mixture in amounts in excess of the amount of RuBPC. When this protein is dissolved in the denatured gut fluids ofM. sexta larvae orSchistocerca gregaria nymphs, large amounts of tannic acid must be added to bring about the precipitation of significant quantities of protein. The ability of insect gut fluid to prevent the formation of insoluble tannin-protein complexes is due to the presence of surfactants. On the basis of our results and a review of the findings of other investigators, we argue that there is no evidence that tannins reduce the nutritional value of an insect's food by inhibiting digestive enzymes or by reducing the digestibility of ingested proteins and, further, that the failure of tannins to interfere with digestion is readily explained on the basis of well-documented characteristics of the digestive systems of herbivorous insects. In challenging the currently popular notion that tannins are digestibility-reducing substances, we do not challenge the general utility of either the apparency theory or resource availability theory of plant defense. In debating the merits of these two analyses of plant-herbivore interactions, however, the demise of tannins as all-purpose, dose-dependent, digestibility-reducing defensive substances must be taken into account.     

机制砂岩性与级配对混凝土抗硫酸盐侵蚀性能的影响

为了探究不同岩性、不同级配机制砂对混凝土性能的影响,对三种不同岩性机制砂混凝土及天然河砂混凝土的工作性和抗压强度进行研究。此外,对比分析了四种混凝土在干湿循环制度下的抗硫酸盐侵蚀性能。结果表明,天然河砂混凝土的工作性优于机制砂混凝土,钙质机制砂混凝土的工作性略好于硅质机制砂混凝土。机制砂混凝土的抗压强度优于天然河砂混凝土,在硫酸盐侵蚀循环作用下的力学性能变化趋势与天然河砂混凝土基本一致。在相同级配条件下,机制砂混凝土的抗蚀系数高于天然河砂混凝土;机制砂岩性并不会对混凝土抗硫酸盐侵蚀性能带来负面影响。级配良好的机制砂可以增强混凝土抗压强度和抗硫酸盐侵蚀性能。     

聚氨酯涂覆胶辊的研制

本文论述了彩色金属薄板生产用聚氨酯涂覆胶辊材料的合成原料选择、配方设计和工艺路线、以及力学性能和溶胀性能等．从测试数据看出．与美国进口样品相比．其力学性能和溶胀性能普遍优于后者。     

Functional properties of proteins in foods

The measurement of functionality of protein food ingredients has developed somewhat haphazardly, probably due to the wide range of proteins used as ingredients and the diversity of foods. Studies of the physiochemical properties of proteins should enable prediction of a proteins response to process environments and prove more fruitful than many of the empirical measurements of functionality. The effects of pH, salt type and concentration on the phase behaviour of the oilseed globulin and arachin, demonstrates the complexity of protein solubility and the inadequacies of simple tests that have arisen. Studies of the effects of salts and conditioning on meat fibres, coupled with measurement of the location of water in pellets from water holding tests enable the latter to be applied with increased confidence. Comparison of the endothermic transitions observed on heating with the development of storage and loss moduli allow the contributions of domains of skeletal muscle myosin to gel structure to be investigated.     

Factors affecting levels of some phenolic compounds,digestibility, and nitrogen content of the mature leaves ofBarteria fistulosa (Passifloraceae)

Levels of total phenolics, condensed tannins, acid detergent fiber, pepsin/cellulase digestibility, and nitrogen in mature leaves of 26 individuals of the ant-plant,Barteria fistulosa, have been determined. Analysis of the results in terms of the presence or absence of ants and the position of the branch from which the leaves were collected showed no relationship with concentrations of phenolics or fiber and only a weak relationship with digestibility and nitrogen. By contrast, light intensity strongly influenced levels of phenolics, notably condensed tannins, so that mature leaves of individuals growing in direct sunlight were less digestible and appeared to be of lower quality as food for herbivores than did mature leaves of individuals in shaded positions. Possible reasons for the variation in condensed tannin levels are discussed.     

Effect of some floral scents on host finding by thrips (Insecta: Thysanoptera)

The role of floral scents in host location by flower-dwelling thrips is investigated by experiment in the field. The scent of anisaldehyde significantly increased the catches of seven species of flower-dwelling thripid, but had no significant effect on three species of cereal thripid and one species of flower-dwelling aeolothripid. The catches of white (without UV) traps were increased by a factor of 3.3 to 8.3 in the presence of the scent.     

Aggregation pheromone system of adult gregarious desert locust schistocerca gregaria (forskal)

Six electrophysiologically active aromatic compounds, viz., anisole, benzaldehyde, veratrole, guaiacol, phenylacetonitrile, and phenol, were identified in the volatiles of older-adult male desert locust. Young adults and females of all age groups produced none or only trace quantities of these compounds. Comparison of the aggregation responses of young and older adults to the crude, older-adult, volatile extract and different synthetic blends of the six compounds showed that the aggregation pheromone system of the adult gregarious locust consists of phenylacetonitrile, guaiacol, phenol, and benzaldehyde. Like the crude volatile extract of older males, neither the synthetic blend of the six compounds nor the adult pheromone blend evoked any significant aggregation responses from nymphs. These results confirm our previous report of sexual differentiation in the production of adult aggregation pheromone in the desert locust and of the evidence of two distinct aggregation pheromone systems in the two stages of the insect.     

Measured kinetics of the acid-catalysed hydrolysis of sugar cane bagasse to produce xylose

Experimental trials of the water hydrolysis of bagasse to produce xylose, arabinose and glucose were conducted using a temperature-controlled microwave digester. The experimental variables were temperature, ratio of water mass to bagasse mass, type of bagasse material and reaction time. The pH of the liquid and concentration of dissolved xylose, arabinose and glucose were measured at the completion of each trial. Kinetic modelling of the global rates of formation of monosaccharide products was performed using schemes based on earlier researchers’ models of acid hydrolysis using mineral acids. For the most plentiful product, xylose, the most accurate kinetic model of the global reactions was determined to be two parallel pathways for hydrolysis of xylan to xylose followed by a single pathway for xylose decomposition. The calculated activation energies of the reactions were within the range reported by other researchers for the hydrolysis of a range of lignocellulosic materials using mineral acids.