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利用相平衡原理得出的焦油蒸馏时一次汽化温度的计算方法,其结果与按经验公式的计算结果进行了比较,同时讨论了一次汽化温度与焦油馏分产率及二段蒸发器过热蒸汽用量的关系。  相似文献   

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Whitlockite (WH) is the second most abundant inorganic component of human bone, accounting for approximately 25% of bone tissue. This study investigated the role of WH in bone remodeling and formation in a mouse spinal fusion model. Specifically, morphology and composition analysis, tests of porosity and surface area, thermogravimetric analysis, an ion-release test, and a cell viability test were conducted to analyze the properties of bone substitutes. The MagOss group received WH, Group A received 100% beta-tricalcium phosphate (β-TCP), Group B received 100% hydroxyapatite (HAp), Group C received 30% HAp/70% β-TCP, and Group D received 60% HAp/40% β-TCP (n = 10 each). All mice were sacrificed 6 weeks after implantation, and micro-CT, hematoxylin and eosin (HE) staining, and Masson trichome (MT) staining and immunohistochemistry were performed. The MagOss group showed more homogeneous and smaller grains, and nanopores (<500 nm) were found in only the MagOss group. On micro-CT, the MagOss group showed larger fusion mass and better graft incorporation into the decorticate mouse spine than other groups. In the in vivo experiment with HE staining, the MagOss group showed the highest new bone area (mean: decortication group, 9.50%; A, 15.08%; B, 15.70%; C, 14.76%; D, 14.70%; MagOss, 22.69%; p < 0.0001). In MT staining, the MagOss group demonstrated the highest new bone area (mean: decortication group, 15.62%; A, 21.41%; B, 22.86%; C, 23.07%; D, 22.47%; MagOss, 26.29%; p < 0.0001). In an immunohistochemical analysis for osteocalcin, osteopontin, and CD31, the MagOss group showed a higher positive area than other groups. WH showed comparable bone conductivity to HAp and β-TCP and increased new bone formation. WH is likely to be used as an improved bone substitute with better bone conductivity than HAp and β-TCP.  相似文献   

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—Due to its chemistry, no structural adhesive system (epoxies, acrylics, etc.) is likely to offer an ideal combination of toughness, strength, moisture resistance, and ambient-temperature curing. Therefore, for effective use of adhesives in primary structures, an engineer must be able to identify adhesives that represent an optimum compromise among the different properties. In this paper, we present techniques for screening high-strength, ambient-temperature-curing adhesives for (1) moisture resistance under sustained loading and (2) fracture resistance in a way that is directly related to joint performance.  相似文献   

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Angiogenesis is one of the hallmarks of cancer. Several studies have shown that vascular endothelium growth factor (VEGF) plays a leading role in angiogenesis progression. Antiangiogenic medication has gained substantial recognition and is commonly administered in many forms of human cancer, leading to a rising interest in cancer therapy. However, this treatment method can lead to a deteriorating outcome of resistance, invasion, distant metastasis, and overall survival relative to its cytotoxicity. Furthermore, there are significant obstacles in tracking the efficacy of antiangiogenic treatments by incorporating positive biomarkers into clinical settings. These shortcomings underline the essential need to identify additional angiogenic inhibitors that target numerous angiogenic factors or to develop a new method for drug delivery of current inhibitors. The great benefits of nanoparticles are their potential, based on their specific properties, to be effective mechanisms that concentrate on the biological system and control various important functions. Among various therapeutic approaches, nanotechnology has emerged as a new strategy for treating different cancer types. This article attempts to demonstrate the huge potential for targeted nanoparticles and their molecular imaging applications. Notably, several nanoparticles have been developed and engineered to demonstrate antiangiogenic features. This nanomedicine could effectively treat a number of cancers using antiangiogenic therapies as an alternative approach. We also discuss the latest antiangiogenic and nanotherapeutic strategies and highlight tumor vessels and their microenvironments.  相似文献   

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针对国内甘氨酸生产厂家排放的工业废水中含有多种污染物(一定量的氯化铵、少量的乌洛托品及微量的甘氨酸)的特点,提出采用多效真空降膜蒸发系统兼热泵技术回收废液中的氯化铵,回收氯化铵后排放的冷凝水进入冷凝水净化系统进行处理的综合治理方案。此工艺克服了采用常规蒸发技术从低浓度氯化铵废液中提取氯化铵带来的能耗大、对设备腐蚀性强的缺点,本项治理技术不仅解决了工业废水对环境的污染,而且有较高的经济效益。  相似文献   

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通过对工程建设项目特点剖析,提出了工程建设项目全过程造价管理、全要素造价管理、全风险造价管理、全团队造价管理等四项造价管理技术,针对其特点提出全面造价管理的管理技术要则,并提出要注重事前管理控制、项目信息的收集和加工、加强项目的动态性管理、重视项目管理的科学性和艺术性等各项要求。  相似文献   

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介绍了双塔再生工艺的原理、改造前后的工艺流程 ,运行情况 ,并对改造进行了经济效益分析。  相似文献   

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<正> After June this year China's regions growingmiddle and late rice had widespread blastand sheath/culm blight.Such diseasesplagued 19.2 million hectares.Starting fromJuly the market for new fungicides that cancontrol blast and sheath/culm blight for ricewas more and more active.Makers of traditional pesticides for thecontrol of blast have to contend with fiercecompetition from new pesticides in marketthis year.Kitazine,iprobenfos,isoprothiolane and tricyclazole,oftenused by farmers in the past,are graduallybeing replaced by new varieties with high  相似文献   

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分析了活性石灰回转窑用耐火材料的损坏原因,认为炉衬的附着物质与氧化硅和氧化铁的反应有关,硅酸钙与CaO是结圈的主要成分.改善耐火材料可以提高其使用寿命.  相似文献   

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刘纯  王烟芝 《陶瓷》2012,(5):29-31
首先介绍了国内外外墙外保温材料的现状,以目前国内对无机不燃外墙外保温材料的紧迫要求为本项目提出的背景。笔者核心介绍了本项目的研究内容、工艺路线、技术指标,并总结了项目的创新点,同时评判了项目风险及应采取的措施。  相似文献   

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花杏华 《塑料制造》2009,(12):62-64
针对汽车用塑料灯头的结构特点与工作环境,分析了灯头结构的复杂性、材料性能,注身工艺条件、合理地设计了注射成型模具,采用了组合式下模型芯来完成内孔的复杂成型,同时采用组合式侧抽芯来完成外侧面的卡钩与上面的穿线孔的成型,简化了模具的结构。  相似文献   

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阐述不确定性分析在化工投资项目可行性研究中的重要的性;介绍盈亏平衡分析、敏感性分析、概率分析3种最常用的不确定性分析方法。  相似文献   

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The Pi soil test, a new approach to measure plant-available P, uses strips of filter paper impregnated with iron oxide as a collector for P in the soil suspension. A modified method for impregnating the paper strips with iron oxide was developed by exposing the FeCl3-treated paper to ammonia vapor instead of immersing it in NH4OH solution. The paper strips prepared by the vapor technique had a more uniform deposit of iron oxide, and the P extracted from four soils ranging in pH from 4.5 to 8.2 and fertilized with two P sources and three rates correlated significantly with dry-matter yield (r = 0.751) of maize.The vapor technique was effective in preparing strips impregnated with both Fe and Al oxides. The ratio of Fe and Al on the strips was about the same as that in the solutions in which the papers were immersed. Strips containing iron oxide alone extracted more P than did strips containing both Fe and Al oxides. The dry-matter yield and P uptake of maize correlated significantly with P extracted by the strips impregnated with Fe, Al, or (Fe + Al) oxides. Phosphorus extracted by the paper impregnated with Fe oxide, and a mixture of Fe and Al oxide in the ratio of 2:1 correlated best with dry-matter yield (r = 0.751 and r = 0.736) and P uptake (r = 0.776 and r = 0.777).  相似文献   

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介绍了用于纺丝油剂用磷酸酯类单体的混合指示剂法、电位滴定法、核磁共振法、色谱法等分析方法,表述了各方法的优缺点,指出结合多种分析方法对该类单体进行分析是今后实现其结构和组成定量分析的方向。  相似文献   

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