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1.
建设创新型国家是我们中华民族的历史责任。“自主创新、重点突破、支撑发展、引领未来”的16字方针应当成为我们未来创新活动的指南。建设创新型国家把自主创新放在首位,并提出了引领未来的高标准要求。钢铁科技创新必须突出重点,抓住创新成果产业化这个关键,支撑起行业和国民经济的发展。  相似文献   

2.
Solid solutions of diphosphates of zinc and copper and of zinc and cobalt were synthesized from mixtures of pure diphosphates at temperatures up to 1000°C. Their X-ray diffractometry patterns varied continuously from one end member to the other. Solid solutions of orthophosphates of composition Zn3−xCox(PO4)2, with x = 0.4–1.6, were formed at temperatures up to 950°C; all exhibited the structure of γ-Zn3(PO4)2. Solid solutions of orthophosphates of composition Zn3−xCux(PO4)2 exhibited more-complex behavior. At 1000°C and copper contents of 20–80 mol%, a phase that is related to Cu3(PO4)2, termed here the "ε-phase," predominated. At 850°–950°C and in the region from 20 mol% to ∼33 mol% of copper, the solid solutions (the "η-phase") adopted the structure of graftonite. At 800°–900°C and 10–15 mol% of copper, the solid solutions exhibited a new structure (the "δ-phase"), which we found to be related to the mineral sarcopside. At temperatures 950°C, the solutions that contained 5–15 mol% of copper (the "β-phase") had the structure of β-Zn3(PO4)2, whereas at 800°–850°C, solutions with 5 mol% of copper (the "-phase") exhibited the structure of γ-Zn3(PO4)2. Attempts to synthesize Cu+ZnPO4 and Cu+Cu2+Zn3(PO4)3 were unsuccessful.  相似文献   

3.
相比已经完善丰富的开采和勘探技术,油气的运输以及储存却仍然存在不足之处。我国对能源安全提出更加严格要求的同时,对区域经济的发展规划也有足够重视。因此,保障油气管道的安全则成为了我国能源安全战略的重中之重。在阐释油气管道现阶段在储运安全保障技术发展状况的基础上,分析了现存的问题及解决问题的手段,并指出未来可能使用的目标策略,为今后研究者提供一定程度上的借鉴经验。  相似文献   

4.
膜的污染和劣化及其防治对策   总被引:25,自引:0,他引:25  
较为系统地介绍了膜污染和劣化的定义和特点,因膜污染和劣化而造成的膜性能变化,以及如何预防、减少或清除膜污染和劣化的一些通用方法。  相似文献   

5.
防水透气聚氨酯薄膜及涂层的研究和应用   总被引:4,自引:0,他引:4  
综述几种防水透气聚氨酯薄膜及涂层的结构、防水透气原理及其成型加工工艺。阐述防水透气聚氨酯薄膜及涂层在衣物及医用制品如高档服装、运动服、手术服、伤口敷料及手术巾等方面的应用。指出防水透气聚氨酯薄膜及涂层具有广阔的应用前景。  相似文献   

6.
陈勇  谢洪泉 《弹性体》2005,15(2):67-72
SBS是(苯乙烯-丁二烯-苯乙烯)三嵌段共聚物,是含有聚苯乙烯玻璃化微区及聚丁二烯连续相的多相聚合物,具有热塑性橡胶的性质。它具有良好的拉伸性能、耐湿性、透气性、溶解性及抗滑性,而被大量用于橡胶制品、粘舍剂及沥青和树脂的改性剂等。其缺点是耐油性差,与极性物质不相容,不粘接等。用环氧化及顺酐化改性可改进这方面的缺点。SBS的环氧化改性多半使用过甲酸或过乙酸在溶液中进行。产物可作为压敏胶、热熔胶、密封胶等,用于粘接极性材料,也可作为耐油热塑性橡胶。SBS的顺酐化改性可在熔融态进行,也可在溶液中进行。产物可用作极性聚合物与非极性聚合物的共混增容剂、胶粘剂及进一步合成离聚体。  相似文献   

7.
The composition and solubility properties of eight ammonium and potassium orthophosphites and hypophosphites were determined to evaluate the potential of these classes of materials for increasing the plant nutrient content of liquid fertilizers. Phase relationships for the systems (NH4)2O-P2O3-H2O, K2O-P2O3-H2O, (NH4)2O-P2O-H2O, and K2O-P2O-H2O were determined along with the crystallographic properties (X-ray and optical) of the solid phases. Toxicity and phosphite response was tested in greenhouse experiments for the compounds.  相似文献   

8.
通过引用Excel对象实例和ADO对象,解决VB中的数据与Excel数据导入、导出的问题.  相似文献   

9.
Tetra(arylalkynyl)pyridines and tetra(arylalkenyl)pyridines and their benzene analogues were prepared by palladium‐catalyzed cross‐coupling reactions from the commercially available chlorinated substrates in good to excellent yields. The photophysical properties of selected compounds were investigated and compared to each other. Very good fluorescence quantum yields were observed, especially for the pyridine derivatives.  相似文献   

10.
李影 《云南化工》2019,(1):167-168
油气田的开发建设一直是我国石油行业中的重中之重。随着我国石油行业的快速发展,各项领域对石油与天然气的需求也越来越大。但是,随着石油与天然气的大力开采,对环境产生了不良的影响。对此,通过对油气田的开发、油气田开发建设对环境的影响以及环境的保护对策等方面进行了简略的说明,希望对我国以后油气田开发建设有一定的指导作用。  相似文献   

11.
研究了填料-橡胶的相互作用。发现N330-NR间的相互作用。n-SiO2(粒径:15nm)/KH-846-NR间的相互作用,都是化学作用占优势(>80%),化学作用对补强的贡献率都大于90%;无偶联剂KH-846时,n-SiO2和SiO2(粒径:15.8nm)与NR都无化学作用,只有物理交联,由于隔离作用,都降低硫化体系与橡胶相互作用的化学交联密度,但n-SiO2的物理交联密度是SiO2的2.6倍,对补强的贡献是SiO2的1.9倍,也是n-SiO2/KH-846体系的61%。  相似文献   

12.
A second-generation enantiospecific synthesis of spiroleucettadine is described. The original reported antibacterial activity was not observed when the experiment was repeated on the synthetic samples; however, significant anti-proliferative activity was uncovered for both enantiomers of spiroleucettadine. Comparison of the optical rotational data and ORD-CD spectra of both enantiomers and the reported spectrum from the natural source have not provided a definitive answer regarding the absolute stereochemistry of naturally occurring spiroleucettadine. Efforts then focussed on alteration at the C-4 and C-5 positions of the slightly more active (−)-spiroleucettadine. Ten analogues were synthesised, with three analogues found to possess similar anti-proliferative profiles to spiroleucettadine against the H522 lung cancer cell line.  相似文献   

13.
绿色火炸药及相关技术的发展与应用   总被引:11,自引:1,他引:11  
王昕 《火炸药学报》2006,29(5):67-71
综述了绿色火炸药及其生产工艺、销毁以及回收利用方面具有“绿色”特征的改进和应用研究成果。绿色火炸药包括洁净固体推进剂、无铅双基推进剂、TPE发射药、无毒发射药、无铅点火药和起爆药。绿色制造技术包括N2O5作硝化剂的含能硝基化合物化学合成,过硝酸盐作硝化剂、微生物作催化剂的生物合成技术,连续化柔性制造技术,基于双螺杆混合成型火炸药生产技术,火炸药生产中挥发性污染物的安全消除技术和纳米复合含能材料的Sol-Gel制备技术。绿色销毁和回收利用技术包括销毁产品的熔盐氧化技术、摧毁含含能化合物废水的光催化技术以及火炸药的回收再利用(R^3)技术。评述了上述火炸药及相关技术的最新状况和发展方向,附参考文献25篇。  相似文献   

14.
文章采用离子色谱法/电导检测器,测定了蔬菜水果样品中的硝酸盐和亚硝酸的含量。实验选取并优化样品前处理方法,获得无色透明的溶液后,经0.45μm过滤器过滤后得到待测液,最后自动进样,离子色谱法进行样品测定,以10 mmol/L KOH溶液为淋洗液,相对标准偏差:NO3-为0.38%,NO2-为0.54%;回收率:NO3-为98.8%~99.7%,NO2-为98.6%~99.9%。本方法操作简便快速,且具有仪器稳定性好、测定结果准确可靠的特点。在被测定蔬菜水果中,硝酸盐和亚硝酸盐含量都在较低浓度水平,NO3-:16.8~21.9 mg/kg,NO2-:0.0887~0.164 mg/kg。最后讨论了几种蔬菜水果样品储藏过程中硝酸盐与亚硝酸盐的含量变化情况。  相似文献   

15.
为了提高油田的生产效率,设计最佳的油气集输处理的工艺流程,更好地完成油气水分离处理的任务。对油气集输工艺技术进行优化,发挥高效油气水分离处理设备的优势,提高油气水处理的质量,保证油气集输工艺顺利实施,获得最佳的油田产量外输。  相似文献   

16.
《Ceramics International》2016,42(13):14313-14325
Bioactive glasses and glassceramics have been used in both bone repair and tissue engineering applications. An important feature of bioactive glasses and glassceramics, which enables them to be used for desired application, is their biological activity. This activity is manifested by the ability of these materials to form a stable bond with bone tissue (bioactivity) and, in some cases, their ability to promote/initiate osteogenesis (osteoinductivity). A stable material-bone bonding (i.e. bioactivity) results from specific material surface reactions leading to hydroxyapatite (HAp) formation on the material surface. Bioactivity of materials is often evaluated in vitro and the ability of materials to form HAp-like surface layer is usually studied after immersion/incubation of materials in simulated body fluid (SBF). Biological activity of materials can be also defined as their ability to induce specific cell responses leading to faster regeneration of bone tissue. It may be manifested by materials supporting bone cell attachment, proliferation and differentiation (biocompability/osteconductivity), and/or by materials inducing/promoting the expression of multiple bone-related genes that drive osteogenesis (osteoinductivity). Osteoinductivity is often verified in vivo by the materials capability to form bone at etopic (i.e. extraskeletal) sites. However, a lot of in vitro call-based experiments are now offered to determine osteoinductive properties of biomaterials. This review focuses on the silica-based glasses and glass-ceramics, in particular, the sol-gel derived ones, and summarizes their bioactivity and osteoinductivity as major determinants of their biological activity. We highlight the chemistry of bioglasses and glassceramics that affects not only the formation of a stable implant/bone bonding by HAp layer, but also drives the cell response in vitro and in vivo.  相似文献   

17.
For continued good health, we are urged to design our meals around the colours of the rainbow. To answer the question “Why?” requires consideration of two evolutionary stories. These broadly are natural evolution, and evolution driven by the activities of human beings. For the first, we need to go back to the start of life on earth and think about pigments rather than colour. There are two major pigment families, carotenoids and those based on the porphyrin ring, without both of which life on earth would not exist, and which still play major roles in our make‐up and well‐being. Other pigments, edible and poisonous evolved as pressures on plant life increased through predation and their own need for survival. The second story commenced with the arrival of human beings and their eventual ability to control fire leading to development of food preservation, processing and more recently, ultraprocessing. The rainbow rule does not apply to such foods in which colour is an indicator of process. Heavily processed foods include use of coloured, cheap, poor quality, and unhealthy ingredients contributing to the present health crisis. For this intervention by humans we must switch from consideration of pigment to that of colour, because it is colour that is a major factor in our selection of the food we eat today.  相似文献   

18.
近年来,随着太阳能被引入微生物燃料电池领域,微生物电化学-光电化学协同产电、产燃料或净化环境的技术成为研究热点。太阳能转化的常用媒介是金属氧化物,探究其与微生物间的相互作用对认清协同机理、提高体系效率等方面有重大意义。综述了不同类型的金属氧化物-微生物相互作用的研究工作,包括微生物-金属氧化物间物理吸附作用、微生物对金属氧化物的矿化和风化作用、微生物-金属氧化物协同产电产燃料系统、金属氧化物光催化杀菌以及光电-微生物电化学协同治理有机污染物或重金属污染,提出了更高效的微生物电化学-光电化学体系的构建方法,为微生物-光催化材料协同体系的实际应用提供帮助。  相似文献   

19.
M.J. López  I. Cabria  J.A. Alonso 《Carbon》2005,43(7):1371-1377
We have studied the relative stability of narrow-finite length Carbon nanotubes and nanostrips as a function of their length. We find that the critical radius (∼2 Å) for tube stability is independent of the length of the tubes and equals the critical radius of infinite length tubes. The independence of the critical radius on chirality is also established. We have also investigated the thermal stability of short nanotubes and nanostrips by performing extensive molecular dynamics simulations. The strips exhibit a higher thermal stability than the tubes even in those cases when they are structurally less stable. The thermal decomposition temperature (∼1000 K) of the tubes comes out in good agreement with the experiments.  相似文献   

20.
油气储运系统已经与保障国家经济的发展息息相关,介绍了油气储运系统中油气回收问题及腐蚀与防护问题,并提出了相应的解决措施。  相似文献   

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