First-principle study on phase Al_0.8Ni₃Sn_0.2 in Sn-Ni-Al alloy as anode for lithium ion battery     

黄钊文  胡社军  侯贤华  赵灵智  汝强  李伟善  张志文 《海洋学报(英文版)》2010,29(11)

The mechanism of lithium intercalation/deintercalation for phase Al_0.8Ni₃Sn_0.2 as anode material used in lithium ion battery was studied carefully based on the first-principle plane wave pseudo-potential method. The calculated results indicated that Sn--Ni--Al alloy had high theoretical capacity when used as anode material, however, there was high initial irreversible capacity loss because of the large volume expansion. Therefore the technological parameters during preparing the Sn-Ni-Al anode should be controlled strictly to make the content of Al_0.8Ni₃Sn_0.2 phase as low as possible and to make the anode consist of promising Sn--Ni and Al--Ni phases. For comparison, an experiment based on magnetron sputtering was done. The result showed that the calculation is in good agreement with the experiment. We found that the first-principle investigation method is of far-reaching significance in synthesising new commercial anode materials with high capacity and good cycle performance.  相似文献   

Origin of iron and aluminium in large particles (> 53 µm) in the Crozet region, Southern Ocean     

Hlne Planquette  Gary R. Fones  Peter J. Statham  Paul J. Morris 《Marine Chemistry》2009,115(1-2):31-42

Natural iron fertilization processes are occurring around the Crozet Islands (46°26′S–52°18′E), thus relieving the water masses from the normally encountered High Nutrients Low Chlorophyll (HNLC) conditions of the Southern Ocean. During austral summers 2004/2005 and 2005/2006, iron and aluminium concentrations were investigated in large particles (> 53 µm) collected from just below the mixed layer at stations under the influence of island inputs, and also in adjacent HNLC waters. These large particles are anticipated to sink out of the mixed layer, and to reflect the net effects of input and cycling of these elements in the overlying mixed layer. Labile and refractory fractions were determined by a two-stage leaching technique. Data showed that water masses downstream of the islands were enriched in total iron and aluminium (0.25–2.68 nmol L^− 1 and 0.34–3.28 nmol L^− 1 respectively), relative to the southern HNLC control sites (0.15–0.29 nmol L^− 1 for Fe and 0.12–0.29 nmol L^− 1 for Al), with only a small fraction (typically < 1%) being acid leachable in both environments. Particulate iron predominantly derived from the island system represents a significant fraction of the total water column iron inventory and may complement dissolved Fe inputs that help support the high summer productivity around the Crozet islands.  相似文献   

添加钛元素对热浸镀锌层性能的影响     

闫瑞华  张克  孙虎元  孙立娟  刘增文 《海洋科学》2008,32(11):20-23

为研究耐蚀性更高但生产成本与传统热镀锌成本相当的新镀层,制备了添加微量钛元素的热浸镀锌层,分别从表观质量、镀层厚度、电化学测试、盐雾腐蚀试验和全浸实验考察了添加微量钛元素对热浸镀锌层性能的影响,扫描电镜观察盐雾试验后镀层表面形貌。结果表明,添加微量钛以后镀层表观质量有所提高,镀层厚度明显减薄,镀层在海水中耐蚀性能提高。微量钛添加量为0．03％～0．04％时耐蚀效果最佳。  相似文献   

微区原位X射线荧光光谱法测定银合金及首饰   总被引：1，自引：0，他引：1  

刘瑱  刘玉纯  梁述廷  林庆文 《安徽地质》2014,(3):213-214

利用带微区分析功能的新型X射线荧光光谱仪,对银合金及首饰中Ag、Cu、Zn等元素进行微区原位分析,建立合理的定量分析方法。该方法具有良好的精密度和准确度,可应用于银合金及首饰的无损检测,并象电子探针测量那样避开焊点,准确地测定各元素的含量。  相似文献   

Effects of alumina refinery wastewater and signature metal constituents at the upper thermal tolerance of: 1. The tropical diatom Nitzschia closterium     

Harford AJ  Hogan AC  Tsang JJ  Parry DL  Negri AP  Adams MS  Stauber JL  van Dam RA 《Marine pollution bulletin》2011,62(3):466-473

Ecotoxicological studies, using the tropical marine diatom, Nitzschia closterium (72-h growth rate), were undertaken to assess potential issues relating to the discharge from an alumina refinery in northern Australia. The studies assessed: (i) the species’ upper thermal tolerance; (ii) the effects of three signature metals, aluminium (Al), vanadium (V) and gallium (Ga) (at 32 °C); and (iii) the effects of wastewater (at 27 and 32 °C). The critical thermal maximum and median inhibition temperature for N. closterium were 32.7 °C and 33.1 °C, respectively. Single metal toxicity tests found that N. closterium was more sensitive to Al compared to Ga and V, with IC₅₀s (95% confidence limits) of 190 (140-280), 19,640 (11,600-25,200) and 42,000 (32,770-56,000) μg L⁻¹, respectively. The undiluted wastewater samples were of low toxicity to N. closterium (IC₅₀s > 100% wastewater). Environmental chemistry data suggested that the key metals and discharge are a very low risk to this species.  相似文献   

安装形状记忆合金阻尼器的剪力墙结构抗震性能分析   总被引：1，自引：0，他引：1  

王立军  毛晨曦  董金芝 《世界地震工程》2011,27(3)

为减轻钢筋混凝土剪力墙连梁的地震后永久性损伤,同时保持连梁的耗能机制,本文提出在剪力墙连梁中安装新型形状记忆合金(Shape Memory Alloy,简称SMA)阻尼器,并研究该阻尼器对剪力墙结构地震响应的减震效果。通过一幢12层剪力墙结构地震反应的时程分析,研究了SMA阻尼器的附加刚度比和屈服位移比两项特征参数对结构地震反应控制效果的影响规律。计算分析结果表明,当附加刚度比为0.04～0.05,屈服位移比为0.4～0.5时,可以获得较好的减震效果。  相似文献   

地质钻探高强度铝合金钻杆研制及其应用          下载免费PDF全文

孙建华  梁健  张永勤  刘秀美  彭莉  王铁  朱彦彬  王汉宝 《探矿工程》2011,38(7):5-8,62

铝合金钻杆的设计制造技术属高新技术范畴,世界上只有俄罗斯、美国等少数发达国家能够批量生产。简要介绍了我国地质钻探用铝合金管材研制、铝合金钻杆制造关键技术及野外试验情况,并对今后铝合金钻杆的研发和应用方向提出了建议。项目工作成果对今后我国开发特深孔铝合金绳索取心钻杆和超深孔铝合金钻杆具有重要价值。安徽彭桥煤矿区的铝合金钻杆钻探试验最大孔深超过1000 m,应用效果良好,开辟了我国地质钻探铝合金钻杆在中深孔应用的先河。  相似文献   

Spectral response of different eroded soils in subtropical china: A case study in Changting County,China     

LIN Chen  ZHOU Sheng-lu  WU Shao-hua  ZHU Qing  DANG Qi 《山地科学学报》2014,11(3):697-707

Hyper-spectral data is widely used to determine soil properties. However, few studies have explored the soil spectral characteristics as response to soil erosion. This study analysed the spectral response of different eroded soils in subtropical China, and then identify the spectral characteristics and soil properties that better discriminate softs with different erosion degrees. Two methods were compared： direct identification by inherent spectral characteristics and indirect identification by predictions of critical soft properties. Results showed that the spectral curves for different degrees of erosion were similar in morphology, while overall reflectance and characteristics of specific absorption peaks were different. When the first method is applied, some differences among different eroded groups were found by integration of associated indicators. However, the index of such indicators showed apparent mixing and crossover among different groups, which reduced the accuracy of identification. For the second method, the correlation between critical soil properties, such as soil organic matter （SOM）, iron and aluminium oxides and reflectance spectra, was analysed. The correlation coefficients for the moderate eroded group were primarily between -0.3 to -0.5, which were worse than the other twogroups. However, the maximum value of R2 was obtained as 0.86 and 0.94 for the non-apparent eroded and the severe group. Furthermore, these two groups also showed some differences in the spectral response of iron complex state （Fep）, Aluminium amorphous state （Alo） and the modelling results for soil organic matter （SOM）. The study proved that it is feasible to identify different degrees of soil erosion by hyperspectral data, and that indirect identification by modelling critical soil properties and reflectance spectra is much better than direct identification. These results indicate that hyper-spectral data may represent a promising tool in monitoring and modelling soil erosion.  相似文献   

低合金钢在海洋各腐蚀区带的锈层研究   总被引：3，自引：1，他引：2  

李言涛  李延旭  侯保荣  张经磊 《海洋与湖沼》1998,29(6):651-655

１９９５年５月通过对低合金－１６Ｍｎ钢在埕岛海区挂片两年（１９９２年１０月－１９９４年１０月）的腐蚀产物的穆斯堡尔谱测定,研究了低合金钢在飞浅区,潮差区,全浸区和海泥区四个不同海洋腐蚀区带的锈层组成和含量。锈层中的ＦｅＯＯＨ和Ｆｅ３Ｏ４的不同含量说明了内锈层中的β－ＦｅＯＯＨ作为氧化剂参与了阴极作用,加速了干湿交替区低合金的腐蚀。  相似文献   

热压高磷铁基胎体性能及其金刚石钻头研究          下载免费PDF全文

阎冠欣 《探矿工程》2009,36(5):75-77,80

针对在硬而致密岩石中钻进时效低和钻头使用寿命短以及传统金刚石钻头胎体材料价格高等众多难题,采用混料回归试验设计方法,进行了替代碳化钨基金刚石钻头胎体材料的新型铁基胎体配方的试验研究;分析了热压钻头的金刚石出刃与岩石研磨性等岩性之间的内在联系,认为钻头的胎体成分及其性能是关键。因此,从热压金刚石钻头的胎体成分与性能研究入手,经过反复的试验研究与优化组合,研究出热压高磷铁基孕镶金刚石钻头的胎体材料,并试制出金刚石钻头。在室内对可钻性Ⅸ级岩石进行钻进的试验表明：钻进时效平均达到1．91m,钻头平均工作寿命达到60．26m。试验结果表明,高磷铁基眙体是一种性能良好的金刚石钻头胎体材料,且该类型胎体的热压金刚石钻头是一种成本明显降低、具有广谱性能的金刚石钻头。  相似文献