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41.
The layered Li[Li0.07Ni0.1Co0.6Mn0.23]O2 materials were synthesized by sol-gel method with glycine or citric acid as chelating agent. The prepared materials were characterized by means of XRD, SEM and Raman spectroscopy. Li/Li[Li0.07Ni0.1Co0.6Mn0.23]O2 cells were assembled and subjected to charge-discharge studies at different C rates, viz 0.2, 1, 2 and 4 C. Although the samples showed less discharge capacity at 4 C rate the fade in capacity per cycle is lesser than that of capacity fade at 0.2 C rate. The citric acid assisted sample is found to be superior in terms of discharge capacity, capacity retention rate and also in thermal stability to that of sample prepared with glycine as chelating agent.  相似文献   
42.
The modification of chitosan represents a challenging task in obtaining biopolymeric materials with enhanced removal capacity for heavy metals. In the present work, the adsorption characteristics of chitosan modified with carboxyl groups (CTS-CAA) towards copper (II) and zinc (II) ions have been tested. The efficacy of the synthesis of CTS-CAA has been evaluated by studying various properties of the modified chitosan. Specifically, the functionalized chitosan has been characterized by using several techniques, including thermal analyses (differential scanning calorimetry and thermogravimetry), spectroscopies (FT-IR, XRD), elemental analysis, and scanning electron microscopy. The kinetics and the adsorption isotherms of CTS-CAA towards both Cu (II) and Zn (II) have been determined in the aqueous solvent under variable pH. The obtained results have been analyzed by using different adsorption models. In addition, the experiments have been conducted at variable temperatures to explore the thermodynamics of the adsorption process. The regeneration of CTS-CAA has been investigated by studying the desorption process using different eluents. This paper reports an efficient protocol to synthesize chitosan-based material perspective as regenerative adsorbents for heavy metals.  相似文献   
43.
本文以靖安地区浅层老井为例,利用钻井、录井、测井、取心等资料,结合现代测井解释评价技术,对受当时技术条件限制被误判的储层进行再分析研究.制定可行的复查评价标准与流程,确定出油下限,优选补孔潜力井,并结合精细地质研究成果筛选建产目标区,达到挖潜增效和滚动增储的双重目的.对老区日后寻找新储量进行勘探开发具有十分重要的意义.  相似文献   
44.
目的 比较蒙、汉用户在不同界面布局的条件刺激下视觉注意对脑电刺激诱发响应的调节和影响作用。方法 基于Oddball实验范式的事件相关电位技术,采用图文形式和纯文本形式的宫格式、标签式,以及侧面展开式界面布局刺激,结合分析脑电数据和行为数据,探究界面布局设计对蒙、汉用户视觉注意的影响。结果 对视觉注意的早期阶段进行研究后发现,图文形式宫格式布局对汉族用户的视觉注意具有显著的刺激和调节作用,而图文形式侧面展开式布局对蒙古族双语用户的视觉注意有显著的刺激和调节作用。通过P300成分波幅发现蒙、汉用户的情绪发生变化,蒙、汉用户在纯文本形式标签式布局界面的影响下产生消极情绪,波幅降低。结论 在事件相关电位技术中,通过P100成分与P300成分的波幅强度变化,可以作为界面布局刺激条件下衡量比较不同民族地区用户视觉注意与情感体验的观测量。  相似文献   
45.
Plant-derived products and their extracted compounds have been used in folk medicine since early times. Zimbro or common juniper (Juniperus communis) is traditionally used to treat renal suppression, acute and chronic cystitis, bladder catarrh, albuminuria, leucorrhea, and amenorrhea. These uses are mainly attributed to its bioactive composition, which is very rich in phenolics, terpenoids, organic acids, alkaloids, and volatile compounds. In the last few years, several studies have analyzed the huge potential of this evergreen shrub, describing a wide range of activities with relevance in different biomedical discipline areas, namely antimicrobial potential against human pathogens and foodborne microorganisms, notorious antioxidant and anti-inflammatory activities, antidiabetic, antihypercholesterolemic and antihyperlipidemic effects, and neuroprotective action, as well as antiproliferative ability against cancer cells and the ability to activate inductive hepato-, renal- and gastroprotective mechanisms. Owing to these promising activities, extracts and bioactive compounds of juniper could be useful for the development of new pharmacological applications in the treatment of several acute and chronic human diseases.  相似文献   
46.
Cancer is a disease exhibiting uncontrollable cell growth and spreading to other parts of the organism. It is a heavy, worldwide burden for mankind with high morbidity and mortality. Therefore, groundbreaking research and innovations are necessary. Research in space under microgravity (µg) conditions is a novel approach with the potential to fight cancer and develop future cancer therapies. Space travel is accompanied by adverse effects on our health, and there is a need to counteract these health problems. On the cellular level, studies have shown that real (r-) and simulated (s-) µg impact survival, apoptosis, proliferation, migration, and adhesion as well as the cytoskeleton, the extracellular matrix, focal adhesion, and growth factors in cancer cells. Moreover, the µg-environment induces in vitro 3D tumor models (multicellular spheroids and organoids) with a high potential for preclinical drug targeting, cancer drug development, and studying the processes of cancer progression and metastasis on a molecular level. This review focuses on the effects of r- and s-µg on different types of cells deriving from thyroid, breast, lung, skin, and prostate cancer, as well as tumors of the gastrointestinal tract. In addition, we summarize the current knowledge of the impact of µg on cancerous stem cells. The information demonstrates that µg has become an important new technology for increasing current knowledge of cancer biology.  相似文献   
47.
48.
In the present work we have coupled PIXE with fission track dating to characterise obsidian artefacts from about 40 archaeological sites of Colombia and Ecuador. PIXE analysis, carried out with the external beam line of the AGLAE tandem accelerator, yields the content in about 15 elements with Z > 8, whereas fission track dating is applied to ages in excess of about 10 000 years. About 120 artefacts were investigated by PIXE, of which 50 were dated by fission tracks. Ages and compositions were compared to those of obsidians from all known geological sources of the region. We show that this double characterisation allows us to determine the number of obsidian sources exploited in an ancient past and to give some insight into obsidian circulation.  相似文献   
49.
Cupric chloride is used as oxidant to synthesize polypyrrole doped with inorganic mineral (ImDPpy). The formation of ImDPpy was confirmed by 1HNMR, BET, SEM, HRTEM, DSC, FTIR, Raman, XRD, UV–vis and XPS studies. The surface area calculated for ImDPpy is 36.671 m2/g. Surface area of IMDPpy is 4.671 m2/g higher than the reported value of Ppy in the literature. In DSC, ImDPpy display a peak at 88.07 °C (endothermic glass transition temperature, Tg), Tg of ImDPpy is almost identical to that of Ppy-MWCNT composite and is higher than Tg of undoped Ppy. Electrochemical analysis of ImDPpy in 0.01 M NaOH indicated the maximum charge stored in ImDPpy in the form of protons as 8090 mF/g. The maximum hydrogen storage capacity of ImDPpy is found to be 18mAh/g at an applied current density of 1 mA/cm2. The mineral doped in Ppy during polymerization is identified as [Cu2(OH)3Cl] from XPS and Raman analysis.  相似文献   
50.
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