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1.
Yu-Jiao Liu Xiao-Yang Fan Dr. Dong-Dong Zhang Yin-Zheng Xia Dr. Yan-Jun Hu Feng-Lei Jiang Prof. Fu-Ling Zhou Prof. Yi Liu 《ChemMedChem》2020,15(6):552-558
Based on the potential therapeutic value in targeting mitochondria and the fluorophore tracing ability, a fluorescent mitochondria-targeted organic arsenical PDT-PAO-F16 was fabricated, which not only visualized the cellular distribution, but also exerted anti-cancer activity in vitro and in vivo via targeting pyruvate dehydrogenase complex (PDHC) and respiratory chain complexes in mitochondria. In details, PDT-PAO-F16 mainly accumulated into mitochondria within hours and suppressed the activity of PDHC resulting in the inhibition of ATP synthesis and thermogenesis disorder. Moreover, the suppression of respiratory chain complex I and IV accelerated the mitochondrial dysfunction leading to caspase family-dependent apoptosis. In vivo, the acute promyelocytic leukemia was greatly alleviated in the PDT-PAO-F16 treated group in APL mice model. Our results demonstrated the organic arsenical precursor with fluorescence imaging and target-anticancer efficacy is a promising anticancer drug. 相似文献
2.
Effect of operating conditions in removal of arsenic from water by nanofiltration membrane 总被引:2,自引:0,他引:2
The removal of arsenic from synthetic waters and surface water by nanofiltration (NF) membrane was investigated. In synthetic solutions, arsenic rejection experiments included variation of arsenic retentate concentration, transmembrane pressure, crossflow velocity and temperature. Arsenic rejection increased with arsenic retentate concentration. Arsenic was removed 93-99% from synthetic feed waters containing between 100 and 382 μg/L as V, resulting in permeate arsenic concentrations of about 5 μg/L. Under studied conditions, arsenic rejection was independent of transmembrane pressure, crossflow velocity and temperature. In surface water, the mean rejection of As V was 95% while the rejection of sulfate was 97%. The co-occurrence of dissolved inorganics does not significantly influence arsenic rejection. The mean concentration of As in collected permeated was 8 μg/L. The mean rejection of TDS, total hardness and conductivity were 75, 88 and 75% respectively. 相似文献
3.
4.
This paper is a critical review and summary of the analytical procedures currently used by operating water utilities to control ozone treatment processes, considering disinfection as well as the many oxidative applications of ozone in water treatment applications. The role of common interferences in the various methods is described.
In operating U S., Canadian, European, and Japanese water treatment plants currently employing ozone as a primary disinfectant, ozone nearly always is followed by the addition of small quantities of chlorine, chlorine dioxide, or chloramine to provide the residual in the distribution system and to act as a secondary disinfectant. Clearly, the analytical procedures used must distinguish between the various species. This review critically presents these various factors and their implication with respect to “true values” of ozone determined under widely varying conditions. 相似文献
5.
在对有机物中微量砷测定方法综合分析的基础上,选用了砷斑法 ̄[1]与Ag-DDTC法 ̄[2]相结合的方法检测有机物中的微量砷。重点对Ag-DDTC法的操作内容作了两处改进。实验表明,新方法检测有机物中的微量砷快速、准确。 相似文献
6.
Paul Westerhoff David Highfield Mohammad Badruzzaman Yeomin Yoon 《Canadian Metallurgical Quarterly》2005,131(2):262-271
Arsenate breakthrough in column studies with a porous granular ferric hydroxide (GFH) was investigated in model waters and groundwaters. In this study, the use of rapid small-scale column tests (RSSCTs) initially designed for simulating the removal of organic compounds by granular activated carbon was extended for arsenate adsorption onto GFH. Adsorption kinetic studies and a comparison of laboratory RSSCT performance versus pilot-scale performance suggests that proportional diffusivity (PD) RSSCT scaling approaches are more valid than constant diffusivity (CD) approaches for arsenate onto GFH. Adsorption densities from column tests (qcolumn) were calculated at the point in the breakthrough curve when arsenate equaled 10 μg/L in the column effluent. For a simulated 2.5 min empty-bed contact time (EBCT), a model water (pH=8.6) had qcolumn values of 0.99 to 1.5 mgAs/gGFH versus 0.02 to 0.28 mgAs/gGFH with a comparable pH and EBCT in a natural groundwater. The differences were attributed to the silica, phosphate, vanadium, and other adsorbable inorganics in the groundwater. At pH 7.6 to 7.8, qcolumn values from PD-RSSCTs in the three natural waters were comparable (1.5±0.3 mgAs/gGFH) and higher than CD-RSSCT qcolumn values (0.57±0.26 mgAs/gGFH) in the three natural waters. All the RSSCTs captured changes in water quality (source water and pH) and operational regimes (e.g., EBCTs) and could be used to aid in the selection and design of arsenic removal media for full-scale treatment facilities. 相似文献
7.
锑氧粉砷浸出工艺研究 总被引:1,自引:0,他引:1
通过对锑氧粉中砷物相的分析,根据三氧化二砷的性质,采用碳酸钠高温焙烧—碳酸化除砷—真空过滤—水洗—真空过滤工艺,将锑氧粉中的元素砷转变为砷酸钠浸出,对影响浸出的几个因素进行了研究,择取优化条件,砷的浸出率可达到94%左右。 相似文献
8.
《Journal of Industrial and Engineering Chemistry》2014,20(1):133-144
Methacrylamide was grafted on to poly (isophthalamide) (PIPA-g-MAA) to improve its solubility and hydrophilicity. Then, PIPA-g-MAA incorporated high performance cellulose acetate ultrafiltration (CA) membranes were prepared by phase inversion technique and physical properties of the membranes were studied by various analytical methods. The efficiency of these membranes in the removal of arsenic from aqueous stream was studied and an effort has been taken to correlate the separation efficiency with morphology. Overall results suggest that membrane hydrophilicity, structure and performance were improved significantly by the addition of PIPA-g-MAA. Thus PIPA-g-MAA can be considered as an effective modification agent for CA membranes. 相似文献
9.
Baofeng Wang Lirong Li Jinjun Zhang 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(10):1370-1376
Effect of pine sawdust on the removal of arsenic and sulfur during Shanxi Tuanbo-2 coal pyrolysis was investigated. Results showed that adding pine sawdust could increase the removals of arsenic and sulfur during Shanxi Tuanbo-2 coal pyrolysis, and when the ratio of the pine sawdust was 50%, the arsenic removal was the highest; at this ratio, the total sulfur removal also was the highest. Adding pine sawdust also increased pyritic sulfur and organic sulfur removal. Furthermore, results also indicated that adding pine sawdust made arsenic associated with sulfates and monosulfides and arsenic in stable forms escape more easily. 相似文献
10.
Aquifers used for the production of drinking water are increasingly being used for the generation of shallow geothermal energy. This causes temperature perturbations far beyond the natural variations in aquifers and the effects of these temperature variations on groundwater quality, in particular trace elements, have not been investigated. Here, we report the results of column experiments to assess the impacts of temperature variations (5°C, 11°C, 25°C and 60°C) on groundwater quality in anoxic reactive unconsolidated sandy sediments derived from an aquifer system widely used for drinking water production in the Netherlands. Our results showed that at 5 °C no effects on water quality were observed compared to the reference of 11°C (in situ temperature). At 25°C, As concentrations were significantly increased and at 60 °C, significant increases were observed pH and DOC, P, K, Si, As, Mo, V, B, and F concentrations. These elements should therefore be considered for water quality monitoring programs of shallow geothermal energy projects. No consistent temperature effects were observed on Na, Ca, Mg, Sr, Fe, Mn, Al, Ba, Co, Cu, Ni, Pb, Zn, Eu, Ho, Sb, Sc, Yb, Ga, La, and Th concentrations, all of which were present in the sediment. The temperature-induced chemical effects were probably caused by (incongruent) dissolution of silicate minerals (K and Si), desorption from, and potentially reductive dissolution of, iron oxides (As, B, Mo, V, and possibly P and DOC), and mineralisation of sedimentary organic matter (DOC and P). 相似文献