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991.
W元素掺杂CeO2非均相电芬顿催化剂高效处理含油污水   总被引:1,自引:0,他引:1  
制备了W元素掺杂的CeO2复合材料, 通过扫描电子显微镜、 透射电子显微镜、 X射线衍射和X射线光电子能谱等对W-CeO2-0.4催化材料进行表征. 结果表明, 具有不规则片状形貌的W元素掺杂CeO2复合材料提高了单一CeO2的类芬顿催化效果; 将其作为非均相电芬顿催化剂对含油污水的处理效果明显优于电吸附和物理吸附过程. 进一步的参数优化处理实验发现, 在电压为4 V, pH=3时, 采用W-CeO2-0.4作为催化剂的条件下, 对含油污水的净化能力在90 min内达到了99.8%, 总有机碳(TOC)去除率达到了约90%, 化学需氧量(COD)去除率达到了76%.  相似文献   
992.
We have designed a new molecularly imprinted co‐polymer (MIP) for the sensitive detection of streptomycin (STR) in food using enzymes as signal amplification. The MIP was fabricated via co‐polymerization of aniline and o‐phenylenediamine on gold substrate in the presence of STR as template. The assay is based on competitive binding of free STR and glucose oxidase‐labeled STR (GOx‐STR) to the imprinters on the MIP. On addition of glucose, hydrogen peroxide is formed that is detected by differential pulse voltammetry. Under optimal conditions, the decrease of the catalytic current is proportional to the STR concentration in the range from 0.01 to 10 ng mL?1, with a detection limit (LOD) of 7.0 pg mL?1 STR (at 3sB). Intra‐ and inter‐assay coefficients of variation (CVs) are<10.5 %. The system was further validated and evaluated with STR‐spiked samples including honey and milk, and the recovery was between 82 and 124.2 %.  相似文献   
993.
建立了高效液相色谱法直接测定榨菜中的防腐剂、甜味剂、合成着色剂的方法.采用C18柱以甲醇-乙酸按(0.02 mot/L)为流动相,紫外检测波长为230,254 nm,可在25 min内将苯甲酸、山梨酸、脱氮乙酸、对羟基苯甲酸乙酯、对羟基苯甲酸丙酯、糖精钠、乙酰磺胺酸钾(安赛蜜)、天门冬酰苯丙胺酸甲酯(阿斯巴甜)、柠檬黄...  相似文献   
994.
肖春生 《高分子科学》2013,31(12):1697-1705
A series of biodegradable hydrogels based on dextran and poly(L-glutamic acid) were fabricated for effective vancomycin loading and release. The preparation of hydrogels was simply achieved by photo cross-linking of methacrylated dextran and poly(L-glutamic acid)-g-hydroxyethyl methacrylate (PGH) in the presence of photoinitiator 12959. The structures of hydrogels were characterized by FTIR and SEM. The swelling and enzymatic degradation behaviors of hydrogels were examined to be dependent on the poly(L-glutamic acid) content in the hydrogels. The higher content of poly(L-glutamic acid) in the gel, the higher swelling ratio and quicker degradation were observed. More interestingly, the hydrogel with higher PGH ratio showed higher vancomycin (VCM) loading content, which might be due to the electrostatic interaction between carboxylate groups in hydrogel and ammonium group of VCM. In vitro drug release from the VCM-loaded hydrogels in aqueous solution exhibited sustained release of VCM up to 72 h, while the in vitro antibacterial test based on the VCM-loaded hydrogel showed an efficient Methicillin-Resistant S. aureus (MRSA) inhibition extending out to 7 days. These results demonstrated that the biodegradable hydrogels which formed by in situ photo-cross linking would be promising as scaffolds or coatings for local antibacterial drug release in tissue engineering.  相似文献   
995.
Details of the structures of two polymorphs of tris(ethylenediamine)cobalt(III) tetrathioantimonate(V), [Co(C2H8N2)3][SbS4], are reported. The first polymorph crystallizes in the orthorhombic space group Pna21, whereas the second polymorph belongs to the tetragonal space group P42bc. Both structures contain octahedral [Co(en)3]3+ cations (en is ethylenediamine) and tetrahedral [SbS4]3− anions, which are interconnected via various N—H...S hydrogen bonds to form two different types of three‐dimensional network.  相似文献   
996.
高效液相色谱法检测人尿中皮质激素水平   总被引:1,自引:0,他引:1  
建立了高效液相色谱法分析测定尿中皮质激素的方法,该法可同时测定尿中醛固酮、可的松及皮质醇的水平,最低检出限为01mg/L,线性范围05~20mg/L,回收率达95%。方法简便、灵敏度较高,可作为常规手段推广应用。  相似文献   
997.
A sensitive hydrogen peroxide (H2O2) sensor was fabricated based on graphene–Pt (GN–Pt) nanocomposite. The GN–Pt was synthesized by photochemical reduction of K2PtCl4 on GNs, and characterized by atomic force microscope (AFM), transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDS). Electrochemical investigations indicated that the GN–Pt exhibited a high peak current and low overpotential towards the reduction of H2O2. The GN–Pt modified glass carbon electrode displayed a wide linear range (2–710 μM), low limit of detection (0.5 μM) and good selectivity for detection of H2O2 with a much higher sensitivity than that of Pt nanoparticles or graphene modified electrode.  相似文献   
998.
One new sesqui-neolignan compound, namely, sesqui-illisimonan A (1), one new neolignan, illisimonan A (2), and one new phenylpropanoid compound, illisimoid A (3) were isolated from the fruits of Illicium simonsii Maxim. The structures and absolute configurations of these compounds were determined by extensive spectroscopic, including NMR, circular dichroism and calculated electronic circular dichroism methods. The antioxidant activities of compounds 13 were also evaluated. Vitamin E was selected as the positive control (IC50 = 49.73 ± 0.88 μM). Compounds 1 and 2 exhibited in vitro antioxidant activity with an IC50 value of 55.76 ± 1.30 and 59.36 ± 0.50 μM, respectively. However, the compound 3 didn’t show obvious antioxidant activity.  相似文献   
999.
Surgery remains the mainstay for most solid tumor treatments. However, surgeons face challenges in intra-operatively identifying invasive tumor margins due to their infiltrative nature. Incomplete excision usually leads to early recurrence, while aggressive resection may injure adjacent functional tissues. Herein, we report a pH responsive ratiometric surface-enhanced Raman scattering (SERRS) probe that determined physiological pHs with a high sensitivity and tissue penetration depth via an innovative mechanism named spatial orientation induced intramolecular energy transfer (SOIET). Due to the positive correlation between tumor acidity and malignancy, an acidic margin-guided surgery strategy was implemented in live animal models by intra-operatively assessing tissue pH/malignancy of the suspicious tissues in tumor cutting edges. This surgery remarkably extended the survival of animal models and minimized their post-surgical complications, showing promise in precisely identifying invasive tumor boundaries and achieving a balance between maximum tumor debulking and minimal functional impairment.

A novel pH ratiometrically responsive surface-enhanced resonance Raman scattering (SERRS) probe was developed for tumor acidic margin delineation and image-guided surgery.  相似文献   
1000.
在毛细管超薄池光度检测中首次采用吸收光强测量新技术,显著提高了测量的灵敏度和改善了信噪比。在内径50μm的石英毛细管超薄池以及由石英光导纤维构成的十字交叉超薄光学吸收池上,分别测量了系列高锰酸钾溶液吸收光强。吸收光强与高锰酸钾溶液浓度之间呈现良好的线性关系。对于10μg/mL的高锰酸钾稀溶液,毛细管超薄池吸收光强测量的信噪比相对于吸光度测量的有较大的改善。十字交叉池的光程约为40μm,容积约为0.02μL,具有较大的光能量,可望发展成为一种新型的电泳光度检测池。  相似文献   
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