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Evidence of Bio-Organic Mineralization
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作者 Zhang Aiyun Weng Chengmin(Department of Enemy Resources Geology, China University of Geosciences, Beijing 100083) 《Journal of Earth Science》 SCIE CAS CSCD 1994年第1期71-78,共8页
The marine black shale formations of different epochs are widely seen in China. They usually come cul as ore-bearing horizon and contain different ore-forming element. Why are there so many different associated meta... The marine black shale formations of different epochs are widely seen in China. They usually come cul as ore-bearing horizon and contain different ore-forming element. Why are there so many different associated metallic elements in the marine black shale ? Evidence shows that the answer is bio-mineralization. The bio-mineralizahon in the process of formation of metalliferous black shales can be divided intp twp stages. The first stage is the bio-achvities occurring in the surface layer aquatic body of the ocean .The ore-forming elements could be absorbed by only a few species of organisms as a bioconcentrator. The second stage is the biogeochemical process. The anaerobic bacteria decomposed the organic remains and the metal elements were activated, and migrated and combined with organic matter or clay minerals or sulfide. After sediments were buried deeply, the organic matter were cracked by high earth temperature.The metal elements in organic compound were continuously acivated, and migrated to form matamorphic minerals or hydrothermal minerals in original rocks or quartz veins. The biogenetic marks in the black shale are changed or distorted beyond recognition and not easy to be found. 展开更多
关键词 CAMBRIAN black shale VANADIUM TUNICATE bio-mineralization.
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Efficiency of Bio-Fertilizing as One of the Natural Alternatives to Improve the Growth of Khaya senegalensis and Swietenia mahagoni Trees and for Sustainability
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作者 Safaa A. S. Ghorab Nashwa H. Mohamed +2 位作者 Nader A. El-Shanhorey Nabal S. El-Shahat Amr R. Rabie 《Agricultural Sciences》 2024年第2期292-310,共19页
A field experiment was carried out at Ismailia Research Station, Ismailia Governorate from 2020-2022 to improve the growth of Khaya senegalensis and Swietenia mahagoni by using a combination of mineral fertilizer (NPK... A field experiment was carried out at Ismailia Research Station, Ismailia Governorate from 2020-2022 to improve the growth of Khaya senegalensis and Swietenia mahagoni by using a combination of mineral fertilizer (NPK) and biological fertilizer (Azotobacter chroococcum, Bacillus megatherium, and Bacillus circulant) as recommended dose under new sandy soils conditions. Split plot designed with four treatments (Control, (50% Mineral fertilizer (M.) + 50% Biological fertilizer (Bio.)), 100% M. and 100% Bio.) of each species. Vegetative growth, leaf area, tree biomass, stored carbon, basal area, tree volume, and in the soil both of microbial account and mineral content were determined. The experimental results showed no significant differences between studied species among the most studied parameters except for Khaya senegalensis which gave the highest significant difference in root biomass and below-stored carbon than Swietenia mahagoni. Evidently, the highest significant growth parameters were 100% mineral fertilizer followed by (50% M. + 50% Bio.) as compared with control. No significant difference between 100% M. and (50% M. + 50% Bio.) of shoot dry biomass (15.19 and 12.02 kg, respectively) and above-stored carbon (0.28 and 0.22 Mt, respectively). Microbial account and mineral content in soil were improved after cultivation of tree species compared to before planting and control, especially with 50% mineral fertilizer and 50% bio-fertilizer treatment. In conclusion, a treatment containing 50% mineral fertilizer and 50% bio-fertilizer has led to the ideal Khaya senegalensis and Swietenia mahagoni growth in sandy soil for cheaper and sustainable. 展开更多
关键词 Khaya senegalensis Swietenia mahagoni mineral Fertilizer bio-FERTILIZER Growth Parameters Tree biomass Stored Carbon SUSTAINABLE
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Adaptation of a Biomineralization Strategy for Remineralization of Enamel and Dentin
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作者 梁志宏 陈治清 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期60-62,共3页
The bio- inspired strategy of triggered release of Ca^2+ , Pi, F from prosomal compartments was used to induce rapid formation of FHA for potential dental use : Calcium and inorganic phosphate salts were separately ... The bio- inspired strategy of triggered release of Ca^2+ , Pi, F from prosomal compartments was used to induce rapid formation of FHA for potential dental use : Calcium and inorganic phosphate salts were separately loaded into temperature-sensitive liposome composed of 90% DPPC and 10% DMPC. When heated from the room temperature to 35- 37 ℃ , the entrapped calcium, inorganic phosphate and fl^rin released from the liposome,A mixture of Ca- Pi and F-loaded liposome formed apatite. The mineral was indicated by a rapid drop in suspension PH from 7.4 approximately 6. This was illustrated by applying a liposome suspension warmed human dentin and enamel surface which resulted in deposition of apatite onto the tissue substrates. 展开更多
关键词 biomimetic bio-mineralization LIPOSOME matrix vesicle
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Microwave-assisted ionothermal synthesis of hierarchical microcube-like BiOBr with enhanced photocatalytic activity 被引量:4
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作者 Yingchun Miao Zichao Lian +1 位作者 Yuning Huo Hexing Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1411-1417,共7页
Bismuth oxybromide(BiOBr) with a hierarchical microcube morphology was successfully synthesized via microwave-assisted ionothermal self-assembly method. The as-obtained BiOBr was composed of regular multi-layered na... Bismuth oxybromide(BiOBr) with a hierarchical microcube morphology was successfully synthesized via microwave-assisted ionothermal self-assembly method. The as-obtained BiOBr was composed of regular multi-layered nanosheets, which were formed by selective adsorption of ionic liquids on the Br-terminated surface, followed by the formation of hydrogen bond-co-π-π stacking.The synthesized BiOBr exhibited high activity, excellent stability, and superior mineralization ability in the photocatalytic degradation of organic dyes under visible light owing to its enhanced light absorbance and narrow bandgap. Furthermore, photo-generated electrons were determined to be the main active species by comparison with different trapping agents used in the photocatalytic reactions. 展开更多
关键词 Microwave bio BrmicrocubesSelf‐assembly Photocatalytic degradation mineralization ability
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A new synthetic chelating collector for the flotation of oxidized-lead mineral 被引量:4
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作者 Yongkai Zhu Chuanyao Sun Weiguo Wu 《Journal of University of Science and Technology Beijing》 CSCD 2007年第1期9-13,共5页
A new synthetic reagent DPTUHP [diphenyl α-(3-phenylthioureido) hexylpbosphonate] containing a hydrocarbon chain nonpolar group, a thioureido, and a phosphonate easter chelating group, has proven to be an effective... A new synthetic reagent DPTUHP [diphenyl α-(3-phenylthioureido) hexylpbosphonate] containing a hydrocarbon chain nonpolar group, a thioureido, and a phosphonate easter chelating group, has proven to be an effective collector for the flotation of cerussite mineral. The synthetic method utilized the Mannich-type reaction of an N-monosubstituted thiourea, an aldehyde, and triphenyl phosphate in glacial acetic acid solution. The experimental results of flotation of the cerussite mineral show that the collector has stronger collecting ability and higher selectivity in a neutral and a slightly alkaline medium, especially in the pulp of pH=8. Using the measurements by infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) of the cerussite mineral, the collector, as well as the cerussite treated with the collector, the flotation mechanism of cerussite has been discussed. It is concluded that the adsorption of collector on cerussite is a chemical adsorption through the electron donor atoms of the collector chelating the Pb ( Ⅱ ) of cerussite to form chelate. 展开更多
关键词 α-(3-phenylthioureido) hexylphosphonate FLOTATION chelating collector cerussite mineral
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Characterization of bioactive ceramic coatings prepared on titanium implants by micro-arc oxidation 被引量:5
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作者 WANG Yingjun NAN Kaihui +3 位作者 CHEN Xiaofeng NING Chengyun WANG lingyu ZHAO Naru 《Rare Metals》 SCIE EI CAS CSCD 2006年第1期84-89,共6页
Micro-arc oxidation (MAO) is an enhanced chemical technology in an electrolyte medium to obtain coating structures on valve-metal surfaces. Titanium oxide films obtained by MAO in the sodium phosphate electrolyte we... Micro-arc oxidation (MAO) is an enhanced chemical technology in an electrolyte medium to obtain coating structures on valve-metal surfaces. Titanium oxide films obtained by MAO in the sodium phosphate electrolyte were investigated. The films were composed mainly of TiO2 phases in the form of anatase and mille and enriched with Na and P elements at the surface. Their apafite-inducing ability was evaluated in a simulated body fluid (SBF). When immersing in SBF for over 30 d, a preferential carbonated-hydroxyapatite was formed on the surfaces of the films, which suggests that the MAO-treated titanium has a promising positive biological response. 展开更多
关键词 ceramic coatings micro-arc oxidation bio-mimetic mineralization carbonated-hydroxyapatite
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沉积矿床中重要(变价)金属元素与古海洋环境关系综述--以新元古代-早古生代扬子板块周缘为例 被引量:1
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作者 张岩 方维萱 +7 位作者 徐林刚 陈文 张志炳 叶会寿 刘丽红 王文浩 赵亮亮 吴皓然 《地质论评》 CAS CSCD 北大核心 2024年第2期679-704,共26页
对氧化—还原敏感元素和生命必需元素地球化学性质和相关沉积矿产形成机制及其时空分布特征的分析、总结和归纳,有助于对古海洋环境演化与相关沉积矿产形成关系的深入认识,这对沉积矿床学理论的发展具有重要意义。新元古代南华纪—早古... 对氧化—还原敏感元素和生命必需元素地球化学性质和相关沉积矿产形成机制及其时空分布特征的分析、总结和归纳,有助于对古海洋环境演化与相关沉积矿产形成关系的深入认识,这对沉积矿床学理论的发展具有重要意义。新元古代南华纪—早古生代早志留世,扬子板块周缘黑色岩系中依次沉积了举世瞩目的南华纪锰矿、震旦纪—早寒武世沉积磷块岩、早寒武世重晶石矿、镍—钼—钴多金属矿、钒矿和早志留世铀矿的完整沉积矿床系列,不同时代地层、同一时代不同沉积环境地层赋存不同类型的沉积矿产,有必要对其成矿机理进行系统研究、总结和归纳。笔者等在对氧化—还原敏感金属元素、生命必需元素和海底热液元素等元素地球化学性质综述的基础上,兼论了它们在结合黄铁矿矿物学对氧化—还原环境、生物生产力和盆地限制性分析方面具体作用;进一步结合新元古代—早古生代扬子板块古环境演化特征,对扬子板块周缘特定时代中特定沉积矿产的分布、成因机理进行分析、总结和归纳;最终得出扬子板块周缘相关沉积矿产,是在全球氧化事件、冰期—间冰期、Rodina大陆裂解大背景下,海洋中成矿金属元素得到长期积累,在特定时代区域性海水—海底热液—生物作用(根据不同矿种各有侧重)影响下,在相关重要元素地球化学性质的控制下、局部区域特殊氧化—还原环境的控制下形成的特定矿产的初步认识。最后,结合相关沉积矿床研究中存在的问题,提出下一步解决方案与展望。 展开更多
关键词 氧化—还原敏感金属元素 生命必需元素 氧化—还原环境判别方法 扬子板块周缘 南华纪—早志留世 沉积矿产
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富血小板纤维蛋白与Bio-Oss骨粉在上颌窦底外提升术中应用价值对比研究 被引量:4
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作者 丁明会 孔令兵 +1 位作者 杨京宇 丁明智 《河北医学》 CAS 2023年第6期990-995,共6页
目的:探讨富血小板纤维蛋白(PRF)与Bio-Oss骨粉应用于颌窦底外提升术中的临床价值对比研究。方法:选取2020年7月至2022年1月就诊于我院并接受上颌窦底外提升术疗法的患者120例,随机数字表法简单随机分为PRF组58例,Bio-Oss组62例,PRF组... 目的:探讨富血小板纤维蛋白(PRF)与Bio-Oss骨粉应用于颌窦底外提升术中的临床价值对比研究。方法:选取2020年7月至2022年1月就诊于我院并接受上颌窦底外提升术疗法的患者120例,随机数字表法简单随机分为PRF组58例,Bio-Oss组62例,PRF组采用富血小板纤维蛋白(PRF)植入干预手术方式,Bio-Oss组采用Bio-Oss骨粉植入干预手术方式,观察两组患者疼痛情况、手术部位黏膜情况、术后骨缺损再生情况及周围软组织健康状况、骨密度变化情况,两组患者治疗前后血小板衍生生长因子(PDGF)、血管内皮生长因子(VEGF)、转化生长因子-β(TGF-β)指标水平,Pearman分析骨密度与PDGF、VEGF、TGF-β的相关性。结果:PRF组疼痛表现较Bio-Oss组明显降低,PRF组中黏膜颜色正常的患者比例较Bio-Oss组明显更高,黏膜肿胀程度较Bio-Oss组显著降低;PRF组患者出血指数、探诊深度、附着丧失指标水平较Bio-Oss组明显降低,PRF组植骨高度、成骨厚度指标较Bio-Oss组明显升高(均P<0.05);术后1个月两组患者骨密度较术前水平均明显下降,但PRF组骨密度水平比Bio-Oss组更高(P<0.05);Bio-Oss组术后3个月骨密度值较术后1个月明显升高,但明显低于术前水平,且明显低于PRF组(均P<0.05);PRF组中各指标水平较Bio-Oss组显著升高(均P<0.05);Pearson相关性分析骨密度与生长因子PDGF、VEGF、TGF-β指标水平,均呈正相关(P<0.05)。结论:针对患者行上颌窦底外提升术时植入PRF可以促进上颌窦内早期新骨形成,能取得良好的临床效果。 展开更多
关键词 富血小板纤维蛋白 bio-OSS骨粉 上颌窦底外提升术 骨密度 生长因子
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Bio-Oss骨粉混合PRF促进第二磨牙远中成骨的临床疗效 被引量:6
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作者 张景喜 丁明会 +2 位作者 杨占宝 刘志龙 张鑫 《中国美容医学》 CAS 2018年第7期120-122,共3页
目的:探讨Bio-Oss骨粉混合富血小板纤维蛋白(PRF)联合应用在阻生智齿拔除后第二磨牙远中成骨的临床疗效。方法:将120颗下颌近中水平阻生智齿随机分为研究组与对照组。研究组术后牙槽窝放置PRF与Bio-Oss骨粉混合物,对照组术后牙槽窝空置... 目的:探讨Bio-Oss骨粉混合富血小板纤维蛋白(PRF)联合应用在阻生智齿拔除后第二磨牙远中成骨的临床疗效。方法:将120颗下颌近中水平阻生智齿随机分为研究组与对照组。研究组术后牙槽窝放置PRF与Bio-Oss骨粉混合物,对照组术后牙槽窝空置处理。比较两组术后1个月、3个月及6个月第二磨牙远中牙槽骨的新生骨密度以及术后3、6个月的骨高度,并进行统计学分析。结果:研究组术后第1个月、第3个月、第6个月的下颌第二磨牙远中牙槽骨新生骨骨密度与同期对照组新生骨骨密度相比,均明显增高,差异有统计学意义(P<0.05)。研究组术后第3个月、第6个月的下颌第二磨牙远中牙槽骨骨高度无明显吸收,与术前骨高度相比差异无统计学(P>0.05);对照组术后第3个月、第6个月的下颌第二磨牙远中牙槽骨骨高度吸收明显,与术前骨高度相比,差异有统计学意义(P<0.05)。结论:PRF与Bio-Oss骨粉联合应用可促进下颌第二磨牙远中新骨形成,减缓拔牙创牙槽嵴的吸收,值得临床推荐。 展开更多
关键词 下颌水平阻生齿 富血小板纤维蛋白 bio-OSS骨粉 新生骨密度 骨高度
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Effects of bamboo charcoal-based bio-fertilizer on wine bamboo sap yield and nutrient composition 被引量:1
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作者 Weicheng Li Haiyan Sheng 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期1072-1081,共10页
To explore fertilization methods for wine bamboo cultivation in southwestern semi-arid areas of China, this study analyzed annual changes in sap yield and nutrient composition from May 2013 to March 2015 by using bamb... To explore fertilization methods for wine bamboo cultivation in southwestern semi-arid areas of China, this study analyzed annual changes in sap yield and nutrient composition from May 2013 to March 2015 by using bamboo charcoal-based bio-fertilizer (ZT) and organic fertilizer treatments (CK). The study also provided basic data for functional beverage preparation and for application of ZT. The results of the two experimental cycles revealed that under the ZT treatment, sap was available for collection from May, the beginning of the rainy season, to November, the beginning of the dry season. The period of abundance was July to October with the highest yield of sap of 3.18 L stalk-1 in September, 2014, still lower than the moso bamboo sap, which was likely due to the scale of sap production of monopodial bamboos being different from that of sympodial bamboos. In January, trace amounts of sap were still detected, suggesting that the effect of the treatment was significant. Moreover,in the dry season, soil water content and soil temperatures at 10-15 cm depths indicated that the fertilizer had the ability to maintain soil temperatures and moisture. In both fertilizer treatments, the correlation between the collected sap and environmental parameters was significant. In the ZT treatment for the entire 2 years, the effectual environ- mental factors were soil water at 10-15 cm, air tempera- tures, and wind speeds. The same determining factors were observed for the rainy season. In the CK treatments, the effectual environmental factors for the entire year and the rainy season were soil water at 0-5 cm and air moisture. The bamboo charcoal-based bio-fertilizer elevated the potassium, calcium, iron, manganese, copper, and total phosphorus content, simultaneously increasing the sap yield, protein and reducing sugar contents, and with a relative increase in sap pH. The wine bamboo sap con- tained 18 amino acids. Glutamic acid, alanine and proline were the most abundant. Compared to the controls, the treatment showed higher levels of all amino acids. Thus, the ZT treatment could be more beneficial to the development of root systems because the function of heat preservation and moisture retention prolong the sap collection period, increase sap yields, and elevate mineral element, conventional nutrients, and amino acid contents with evident fertilization effects and broader application prospects. 展开更多
关键词 Amino acids Bamboo charcoal-based fertilizer bio-FERTILIZER mineral elements Sympodial bamboo Wine bamboo sap
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矿渣和粉煤灰对微生物-氧化镁协同固化钻屑性能的改良机理
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作者 唐国旺 邓强 +2 位作者 赵中军 周锴 王贵和 《结构工程师》 2024年第2期170-175,共6页
钻屑作为一种固废,其主要处理方式为水泥固化,但加工水泥易产生大量二氧化碳,不利于环境保护。基于上述问题,提出了一种改良后微生物-氧化镁协同固化钻屑新方法。通过强度测试,研究了高炉矿渣和粉煤灰对微生物-氧化镁协同固化钻屑的改良... 钻屑作为一种固废,其主要处理方式为水泥固化,但加工水泥易产生大量二氧化碳,不利于环境保护。基于上述问题,提出了一种改良后微生物-氧化镁协同固化钻屑新方法。通过强度测试,研究了高炉矿渣和粉煤灰对微生物-氧化镁协同固化钻屑的改良,获得了钻屑固化体强度随高炉矿渣掺量增加而升高,随粉煤灰掺量增加而逐渐降低的规律,最高强度为5.4MPa。采用FTIR、XRD和SEM等测试手段,对固化体中产物类型和结构进行了分析,结果表明:产物由连续的水菱镁石(矿化产物)、云雾状水化硅酸镁和层状水滑石(水化产物)组成。钻屑颗粒由矿化产物和少量水化产物固化,揭示了矿渣和粉煤灰在微生物-氧化镁协同固化钻屑的作用机理。 展开更多
关键词 钻屑 粉煤灰 矿渣 生物矿化 活性氧化镁
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Treatment of Dyes Wastewater by a New Kind of Bio - Fluid Bed
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作者 黄永辉 奚旦立 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期120-122,共3页
A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing th... A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing the experiment data,the results show that the dye wastewater’s organic matter is removed greatly after be-ing treated by this new kind of bio-fluid bed.On the other hand,the removal efficiency of chromaticity of 展开更多
关键词 NEW bio - fluid BED removal efficiency DYES wastewater.
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New Advances in Structural Studies of Barium Rare-Earth Fluor-Carbonate Minerals
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作者 Shen Jinchuan Mi JinxiaoChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期21-28,共8页
This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal di... This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal diffractometer . Five kinds of coordination forms were found . All atoms in the cell , including C and F , were properly located . In the process of study in a cordylite-(Ce ), a new mineral was discovered , whose chemical formula is (Ca0.5□0.5) BaCe2 (CO3)4F . It is isostructural with baiyuneboite - (Ce ), but different in composition (Na in baiyuneboite- (Ce ) is substituted by Ca disorderly ) . On the basis of the studies a proposal to re-define cordylite-(Ce )as a mineral group name is put forth by the authors . Finally a new type of twinning of huanghoite-(Ce ) was found on the systematical absence of diffraction data by means of a single crystal diffractometer . 展开更多
关键词 rare - earth mineral crystal structure cordylite -(Ce) cebaite - (Ce) baiyuneboite - (Ce) huanghoite - (Ce) X - ray analysis .
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华南早寒武世黑色岩系Ni-Mo多金属矿床成因研究进展 被引量:25
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作者 施春华 曹剑 +3 位作者 胡凯 韩善楚 边立曾 姚素平 《地质论评》 CAS CSCD 北大核心 2011年第5期718-730,共13页
通过调研分析我国华南早寒武世黑色岩系Ni—Mo多金属矿床成因研究的现状,述评了这一领域的研究进展,提出了今后深化研究值得加强的方向。将已有提出的矿床成因模式总体归纳为5种观点:陨石撞击同沉积、岩浆火山碎屑、海水、热水、多源,... 通过调研分析我国华南早寒武世黑色岩系Ni—Mo多金属矿床成因研究的现状,述评了这一领域的研究进展,提出了今后深化研究值得加强的方向。将已有提出的矿床成因模式总体归纳为5种观点:陨石撞击同沉积、岩浆火山碎屑、海水、热水、多源,并且认为目前主要侧重于对热水和海水两种成因的研究,这两方面积累的证据较多,争议也较大。结合生物有机质在矿床形成过程中起到了重要作用,即生物有机成矿作用,认为矿床成因复杂,受到热水、海水、生物有机质的多元复合作用。总体而言,各种矿床成因观点均各有证据支持,但因成矿过程复杂,成矿地质作用多样,所以尚不能够完全全面、合理地揭示成矿过程,仍有待进一步深入工作;建议加强原位实验分析测试技术的应用和矿床成因研究的时空对比。这些认识为存在诸多争议和不确定性的该领域研究提供了参考,并且因这一分析对象是全球黑色岩系矿床的一个典型实例,所以认识可望具有普遍参考意义。 展开更多
关键词 Ni—Mo多金属矿床 黑色岩系 热水成矿 海水成矿 生物有机成矿 下寒武统 华南
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微生物浸出中微生物-矿物多相界面作用的研究进展 被引量:35
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作者 柳建设 王兆慧 +1 位作者 耿梅梅 邱冠周 《矿冶工程》 CAS CSCD 北大核心 2006年第1期40-44,共5页
微生物浸出体系涉及微生物-矿物、矿物-矿物、微生物-溶液-矿物-气相等多相界面作用。综合国内外文献报道,针对矿物-水、微生物-矿物和矿物-矿物界面,较全面的阐述了多相界面作用的影响因素、作用机理及其在生物冶金中的应用。最后根据... 微生物浸出体系涉及微生物-矿物、矿物-矿物、微生物-溶液-矿物-气相等多相界面作用。综合国内外文献报道,针对矿物-水、微生物-矿物和矿物-矿物界面,较全面的阐述了多相界面作用的影响因素、作用机理及其在生物冶金中的应用。最后根据目前研究现状提出了近期微生物-矿物多相界面作用的研究趋势。 展开更多
关键词 微生物浸出 多相作用 硫化矿 吸附 生物膜
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混凝土三轴变幅拉-压疲劳性能试验研究 被引量:10
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作者 曹伟 宋玉普 刘海成 《工程力学》 EI CSCD 北大核心 2006年第3期111-117,31,共8页
进行了最小应力水平为0.20fc,最大应力水平为0.20ft^0.55ft,定侧压为0.30fc的变截面混凝土试件三轴拉-压等幅和变幅疲劳试验,分析了混凝土三轴拉-压疲劳最大和最小纵向总应变的三阶段演变规律和级间相似性,给出了疲劳损伤演化规律。进... 进行了最小应力水平为0.20fc,最大应力水平为0.20ft^0.55ft,定侧压为0.30fc的变截面混凝土试件三轴拉-压等幅和变幅疲劳试验,分析了混凝土三轴拉-压疲劳最大和最小纵向总应变的三阶段演变规律和级间相似性,给出了疲劳损伤演化规律。进一步验证了Miner线性损伤累积理论的不适用性,提出了非线性损伤累积模型,并进行了疲劳剩余寿命预测,通过与试验结果的比较表明该模型具有较高的精度和适用性。 展开更多
关键词 混凝土 三轴拉-压疲劳 三阶段规律 miner准则 非线性损伤累积模型
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CaO—P_2O_5—SiO_2系统溶胶-凝胶玻璃的生物矿化行为 被引量:12
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作者 陈晓峰 王迎军 +1 位作者 赵娜如 郑裕东 《材料研究学报》 EI CAS CSCD 北大核心 2003年第3期268-275,共8页
利用体外实验方法(in vitro)以及XRD、SEM、FTIR、BET、ICP等手段研究了两种溶胶-凝胶生物活性玻璃的显微结构及其在模拟生理溶液(SBF)中的降解过程、表面反应产物和生物矿化机理。结果表明,两种生物活性玻璃都具有较高的生物活性,均具... 利用体外实验方法(in vitro)以及XRD、SEM、FTIR、BET、ICP等手段研究了两种溶胶-凝胶生物活性玻璃的显微结构及其在模拟生理溶液(SBF)中的降解过程、表面反应产物和生物矿化机理。结果表明,两种生物活性玻璃都具有较高的生物活性,均具有由纳米尺寸颗粒相互连接而成的微孔结构和较大的比表面积,在模拟生理溶液(SBF)中浸泡后可形成表面类似天然骨中无机矿物的碳酸羟基磷灰石层(HCA),说明两者均具有较高的生物活性和生理环境相应特性。材料表面的硅酸凝胶层及其硅羟基团的形成对碳酸羟基磷灰石(HCA)微晶的成核有重要作用。 展开更多
关键词 无机非金属材料 生物活性材料 模拟生理溶液 可降解性 生物矿化
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PLA-PEG-PLA/PLA组织工程支架在模拟体液中的降解和生物矿化性能 被引量:5
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作者 葛建华 王迎军 郑裕东 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2011年第11期126-128,132,共4页
系统研究了含有聚乳酸-聚乙二醇-聚乳酸嵌段共聚物(PLA-PEG-PLA)的聚乳酸组织工程支架在模拟体液(SBF)中的降解和生物矿化性能。通过研究可以得到如下结论:随着含有PLA-PEG-PLA共聚物的聚乳酸组织工程支架在模拟体液中浸泡时间的增长,... 系统研究了含有聚乳酸-聚乙二醇-聚乳酸嵌段共聚物(PLA-PEG-PLA)的聚乳酸组织工程支架在模拟体液(SBF)中的降解和生物矿化性能。通过研究可以得到如下结论:随着含有PLA-PEG-PLA共聚物的聚乳酸组织工程支架在模拟体液中浸泡时间的增长,模拟体液的pH值有下降趋势;支架材料的质量有升有降,是降解和矿化作用共同影响的结果。X射线衍射图谱和FT-IR漫反射图谱研究表明,浸在SBF中的支架表面有磷灰石沉积物出现,并且PLA-PEG-PLA共聚物降解速度比PLA快。 展开更多
关键词 聚乳酸-聚乙二醇-聚乳酸嵌段共聚物 组织工程 降解 生物矿化
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溶胶-凝胶生物活性玻璃纤维的制备及其体外矿化性能研究 被引量:4
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作者 李玉莉 陈晓峰 +1 位作者 王迎军 赵娜如 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2007年第4期617-621,共5页
采用溶胶-凝胶法制备出CaO-P_2O_5-SiO_2系统生物活性玻璃纤维.通过倒置相差显微镜、SEM、FTIR等测试手段考察了生物活性玻璃纤维的微观形貌和显微结构;采用生物材料的体外实验方法以及XRD、SEM、FTIR等测试手段研究了生物活性玻璃纤维... 采用溶胶-凝胶法制备出CaO-P_2O_5-SiO_2系统生物活性玻璃纤维.通过倒置相差显微镜、SEM、FTIR等测试手段考察了生物活性玻璃纤维的微观形貌和显微结构;采用生物材料的体外实验方法以及XRD、SEM、FTIR等测试手段研究了生物活性玻璃纤维在模拟生理体液(SBF)中浸泡后的表面反应产物的形成机理、结晶程度和微观形貌.结果表明,这种生物活性玻璃纤维是一种不连续的短纤维,具有较好的纤维形态和较高的生物活性,在短时间内即可在模拟生理体液(SBF)中形成茸毛状A类碳酸羟基磷灰石(HCA)层. 展开更多
关键词 生物活性纤维 溶胶-凝胶 生物矿化 模拟生理体液
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考虑车-桥耦合的重载铁路钢桥局部疲劳分析 被引量:13
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作者 朱志辉 冯乾朔 +2 位作者 龚威 蒋丽忠 余志武 《铁道工程学报》 EI 北大核心 2019年第9期36-42,78,共8页
研究目的:基于车-桥耦合振动理论,以64 m简支钢桁梁桥为实例,研究重载铁路钢桁梁桥局部疲劳可靠度问题。首先建立64 m简支钢桁梁桥的车-桥动力学模型,通过现场试验结果验证模型的准确性,并确定桥梁最不利疲劳部位;然后基于Monte Carlo方... 研究目的:基于车-桥耦合振动理论,以64 m简支钢桁梁桥为实例,研究重载铁路钢桁梁桥局部疲劳可靠度问题。首先建立64 m简支钢桁梁桥的车-桥动力学模型,通过现场试验结果验证模型的准确性,并确定桥梁最不利疲劳部位;然后基于Monte Carlo方法,将车速和轨道不平顺作为随机变量,随机选取100个车速和轨道不平顺的组合样本;利用Miner线性疲劳累积准则和概率密度函数方法,得到钢桥最不利疲劳部位的等效应力范围和年疲劳损伤系数的概率分布,并给出桥梁局部疲劳损伤系数与列车编组的关系式;最后分析不同列车类型和行车速度条件对桥梁疲劳损伤的影响。研究结论:(1)在考虑参数随机概率分布的条件下,桥梁最不利疲劳部位的等效应力范围和年疲劳损伤系数均服从Lognormal分布;(2)当货运列车年运量一定时,列车轴重是桥梁局部损伤的主要影响因素,桥梁的疲劳损伤随轴重增加而增大;(3)在设计时速范围内,列车速度与桥梁疲劳损伤的相关性不强;(4)本研究成果可为重载铁路钢桁梁桥设计与疲劳性能评估提供参考。 展开更多
关键词 疲劳 重载铁路钢桁梁桥 -桥耦合振动 miner线性疲劳累积准则 MONTE CARLO方法 概率密度函数
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