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1.
Angew Chem Int Ed Engl ; 61(2): e202113086, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34664355

RESUMO

Solid-state zinc (Zn) batteries offer a new candidate for emerging applications sensitive to volume, safety and cost. However, current solid polymeric or ceramic electrolyte structures remain poorly conductive for the divalent Zn2+ , especially at room temperature. Constructing a heterogeneous interface which allows Zn2+ percolation is a viable option, but this is rarely involved in multivalent systems. Herein, we construct a solid Zn2+ -ion conductor by inducing crystallization of tailored eutectic liquids formed by organic Zn salts and bipolar ligands. High-entropy eutectic-networks weaken the ion-association and form interfacial Zn2+ -percolated channels on the nucleator surfaces, resulting in a solid crystal with exceptional selectivity for Zn2+ transport (t Zn 2 + =0.64) and appreciable Zn2+ conductivity (σ Zn 2 + =3.78×10-5  S cm-1 at 30 °C, over 2 orders of magnitude higher than conventional polymers), and finally enabling practical ambient-temperature Zn/V2 O5 metal solid cells. This design principle leveraged by the eutectic solidification affords new insights on the multivalent solid electrochemistry suffering from slow ion migration.

2.
Angew Chem Int Ed Engl ; 59(48): 21769-21777, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-32812326

RESUMO

Conventional carbonate solvents with low HOMO levels are theoretically compatible with the low-cost, high-voltage chemistry of Zn/graphite batteries. However, the nucleophilic attack of the anion on carbonates induces an oxidative breakdown at high potentials. Here, we restore the inherent anodic stability of carbonate electrolytes by designing a micro-heterogeneous anion solvation network. Based on the addition of a strongly electron-donating solvent, trimethyl phosphate (TMP), the oxidation-vulnerable anion-carbonate affinities are decoupled because of the preferential sequestration of anions into solvating TMP domains around the metal cations. The hybridized electrolytes elevate the electrochemical window of carbonate electrolytes by 0.45 V and enable the operation of Zn/graphite dual-ion cells at 2.80 V with a long cycle life (92 % capacity retention after 1000 cycles). By inheriting the non-flammability from TMP and the high ion-transport kinetics from the carbonate systems, this facile strategy provides cells with the additional benefits of fire retardancy and high-power capability.

3.
Int J Phytoremediation ; 20(8): 839-846, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29775107

RESUMO

Deteriorating urban water quality has attracted considerable attention in China. We investigated the contamination levels and distribution of heavy metals (As, Cd, Cu, Ni, Pb, and Zn) in Yuxi River water and sediments, and assessed the heavy metal accumulation capability of five species of submerged macrophytes: Vallisneria natans (Lour.) Hara, Potamogeton pectinatus L., Hydrilla verticillata (L. f.) Royle, Myriophyllum spicatum L., and Potamogeton crispus L. Samples were collected from upstream and downstream locations in different season. The results showed that the levels of heavy metals in the downstream areas were higher than in the upstream areas. Heavy metal concentrations in the river water during the dry seasons were higher than those during the rainy seasons, and the opposite results appeared in sediments and submerged macrophytes. In general, the river was slightly contaminated by heavy metals, and the concentrations of Pb and Ni in this river should serve as a warning, while Cd and Zn pollution in the sediments desperately needs to be removed. Furthermore, Potamogeton pectinatus L. showed a higher accumulation capacity for these metals among the five native submerged macrophytes and could be defined as a hyperaccumulator for Cd. Therefore, the potential use of native aquatic plants in contaminated rivers is worth further exploration.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Biodegradação Ambiental , China , Sedimentos Geológicos , Rios
4.
Ultrasonics ; 75: 22-27, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27898301

RESUMO

An energy harvesting type ultrasonic motor is presented in this work. The novel motor not only can drive and/or position the motion mechanism, but also can harvest and convert the vibration-induced energy of the stator into electric energy to power small electronic devices. In the new motor, the stator is a sandwich structure of two PZT rings and an elastic metal body. The PZT ring bonded on the bottom surface is used to excite the stator metal body to generate a traveling wave with converse piezoelectric effect, and the other PZT ring bonded on top surface is used to harvest and convert the vibration-induced energy of the stator into electric energy with direct piezoelectric effect. Finite element method is adopted to analyze the vibration characteristics and the energetic characteristic. After the fabrication of a prototype, the mechanical output and electric energy output abilities are measured. The maximum no-load speed and maximum output torque of the prototype are 117rpm and 0.65Nm at an exciting voltage with amplitude of 134 Vp-p and frequency of 40kHz, and the maximum harvesting output power of per sector area of the harvesting PZT is 327mW under an optimal equivalent load resistance of 6.9kΩ.

5.
Water Sci Technol ; 74(6): 1409-1416, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27685970

RESUMO

Although rhizoremediation is an effective approach to remove organic pollutants from the environment, little is known about the mechanism of hexachlorobenzene (HCB) biodegradation in water. In this study, we used Typha angustifolia (T. angustifolia) grown in sterile Hoagland nutrient solution to determine the rhizosphere effects on the ability of bacteria in water to reduce HCB levels. The results revealed that T. angustifolia could facilitate HCB degradation and that the initial HCB concentration was the major factor responsible for HCB degradation in nutrient solution. Furthermore, HCB biodegradation in low-HCB nutrient solution with T. angustifolia fitted the first-order kinetics, owing to the high concentration of total organic carbon, low HCB toxicity, and unique bacterial community in the T. angustifolia rhizosphere. Denaturing gradient gel electrophoresis indicated that the rhizosphere effects and different dosages of HCB have significant effects on the bacterial communities by repressing and favoring certain populations. The most successful bacteria to adapt to HCB contamination was Bacillus sp., while the dominant bacterial phyla in HCB-polluted water were Proteobacteria and Firmicutes.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Hexaclorobenzeno/metabolismo , Typhaceae/metabolismo , Poluentes Químicos da Água/metabolismo , Hexaclorobenzeno/química , Água/análise , Poluentes Químicos da Água/química
6.
Huan Jing Ke Xue ; 34(12): 4654-60, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24640904

RESUMO

Using a portable gas chromatography and mass spectrometry (GC-MS), the volatile organic compounds (VOCs) pollution in each unit of the wastewater treatment system for vitamin C production was studied, and the species characteristics of volatile organic compounds (VOCs) were analyzed and summarized. The results showed that 32 kinds of volatile organic compounds were identified, and the total mass concentration range of volatilizing VOCs was 0.9629-32.0970 mg x m(-3). The most species and the largest concentration (25 and 32.0970 mg x m(-3)) of volatilizing VOCs were found in grit chamber, which was located in the most front-end of the wastewater treatment system and was in semi-closed state. The proportion of molecular sulfide in the grit chamber was as high as 30.02%; Higher proportions of aromatic hydrocarbons were monitored in the subsequent processing units, with percentages of 21.06%-31.48%. The main types of VOCs monitored were chlorinated hydrocarbons and ketones, accounting for 6.39%-55.80% and 10.40%-58.08% of the total amount, respectively; 14 kinds of VOCs were detected in every unit of the wastewater treatment system: acetone, 2-butanone, n-hexane, chloroform, chlorobenzene etc, among which, vinyl chloride, styrene and 1,3-butadiene belong to the highly toxic substances. The vinyl chloride concentration exceeded the standard of "atmospheric pollutants emission standards" (GB 16297-1996), while 1,3-butadiene and other pollutants have no national standard limits. The results of this study provide a scientific basis for the revision of China's pharmaceutical wastewater VOCs emission standards.


Assuntos
Poluentes Atmosféricos/análise , Ácido Ascórbico/química , Monitoramento Ambiental , Compostos Orgânicos Voláteis/análise , Águas Residuárias/análise , Butadienos/análise , Butanonas/análise , China , Indústria Farmacêutica , Cromatografia Gasosa-Espectrometria de Massas , Hexanos/análise , Hidrocarbonetos Aromáticos/análise , Eliminação de Resíduos Líquidos
7.
Fa Yi Xue Za Zhi ; 28(5): 337-41, 346, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23213782

RESUMO

OBJECTIVE: To investigate KCNQ1, KCNH2, KCNE1 and KCNE2 gene variants in the cases of sudden manhood death syndrome (SMDS). METHODS: One hundred and sixteen sporadic cases of SMDS and one hundred and twenty-five healthy controlled samples were enrolled. Genomic DNA was extracted from blood samples. Gene variants of KCNQ1, KCNH2, KCNE1 and KCNE2 were screened by direct sequencing. RESULTS: A total of 14 mutations and 14 SNP were detected. Two non-synonymous mutations of them were newfound. There was no non-synonymous mutation found in the control group. CONCLUSION: There are KCNQ1, KCNH2, KCNE1 and KCNE2 gene variants found in Chinese SMDS cases. KCNQ1, KCNH2, KCNE1 and KCNE2 gene mutation may correlate partly with the occurrence of some cases of the SMDS in China.


Assuntos
Morte Súbita/etnologia , Canais de Potássio Éter-A-Go-Go/genética , Canal de Potássio KCNQ1/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Sequência de Bases , Estudos de Casos e Controles , China , Análise Mutacional de DNA , Canal de Potássio ERG1 , Humanos , Síndrome do QT Longo , Mutação , Polimorfismo de Nucleotídeo Único , Canais de Potássio
8.
Fa Yi Xue Za Zhi ; 28(2): 89-91, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22619800

RESUMO

OBJECTIVE: To explore the postmortem changes of cornea thickness measured by ultrasonic pachymetry. METHODS: Eleven rabbits were randomly divided into two groups: one group with intact corneal epithelium and another group without intact corneal epithelium. In the later group, the corneal epithelium of the rabbit was scraped using mechanical elimination method. The corneal thickness was monitored continuously by ultrasonic pachymetry at several postmortem interval points in rabbits of the two groups. The changes of corneal thickness and postmortem interval were explored by relative regression analysis. RESULTS: The thickness of the cornea showed a strong non-linear correlation with the postmortem interval in the group with intact corneal epithelium. The group with intact corneal epithelium showed the correlation coefficient 0.922 and the group without intact corneal epithelium showed the correlation coefficient 0.822, respectively. CONCLUSION: The corneal thickness measured by ultrasonic pachymetry shows a potential value for estimating early postmortem interval. The intact corneal epithelium is a crucial factor for the measurement of cornea thickness by ultrasonic pachymetry.


Assuntos
Córnea/diagnóstico por imagem , Córnea/patologia , Topografia da Córnea/métodos , Mudanças Depois da Morte , Animais , Epitélio Corneano/patologia , Epitélio Corneano/ultraestrutura , Feminino , Patologia Legal/métodos , Masculino , Coelhos , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Tempo , Ultrassonografia
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(7): 955-8, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17666324

RESUMO

OBJECTIVE: To construct an eukaryotic expression vector for PRL-2 and evaluate its effect on the invasiveness and migration of a human hepatocellular carcinoma cell line. METHODS: RT-PCR was performed to amplify the complete PRL-2 open reading frame using the total mRNA of hepatocellular carcinoma HepG2 cells as the template. PRL-2 gene was inserted into the pGEM T easy vector and sequenced, and the correct PRL-2 sequence was subcloned into the mammalian expression vector pcDNA3.1+. The constructed PRL-2 vector was transfected into CL1 cells via lipofectamine, and the stable expression of PRL-2 mRNA was detected by RT-PCR, the expressed protein identified by immunohistochemistry and Western blotting, and the effect of PRL-2 on the adhesion ability of CL-1 cell evaluated with MTT assay 20 and 120 min after transfection. The effect of PRL-2 on the invasive migration of CL-2 cells was evaluated according to the number of cells penetrating the Matrigel layer of polycarbonate membrane of Boyden chamber. RESULTS: RT-PCR yielded a fragment of 504 bp and the inserted PRL-2 sequence was verified by sequence analysis. The subclones were identified by restriction endonuclease digestion, and a G418-resistant clone, PRL-2-CL1, was obtained after 8 weeks of selection. RT-PCR showed stable expression of PRL-2 mRNA, and Western blotting confirmed overexpression of PRL-2 protein in the transfected cells. PRL-2 increased the adhesion rate of CL-1 cells to fibronectin at 20 min and 120 min after transfection (P<0.05), and also the number of CL-1 cells penetrating the polycarbonate membrane from 10.0+/-3.7 to 44.8+/-2.6 (P<0.05). CONCLUSION: An eukaryotic expression vector of PRL-2 has been successfully constructed, which allows stable and efficient expression in CL-1 cell line. PRL-2 can promote cell adhesion and invasion activity of human hepatocellular carcinoma cells.


Assuntos
Carcinoma Hepatocelular/patologia , Movimento Celular/genética , Células Eucarióticas/metabolismo , Vetores Genéticos/genética , Neoplasias Hepáticas/patologia , Proteínas Tirosina Fosfatases/genética , Animais , Western Blotting , Carcinoma Hepatocelular/genética , Adesão Celular/genética , Linhagem Celular Tumoral , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Invasividade Neoplásica/genética , Proteínas Tirosina Fosfatases/biossíntese , Proteínas Tirosina Fosfatases/isolamento & purificação , Proteínas Tirosina Fosfatases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
10.
Zhonghua Bing Li Xue Za Zhi ; 33(1): 26-30, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-14989924

RESUMO

OBJECTIVE: To investigate gene amplification of CCND1 and expression of cyclin D1 in hepatocellular carcinoma (HCC) and to explore the possible relationship between CCND1 gene status and carcinogenesis of HCC. METHODS: Differential PCR, RT-PCR and immunohistochemistry were used to detect gene amplification, mRNA and protein expression of cyclin D1 in 20 HCC cases respectively. The relationship between the gene amplification rate and the expression level of cyclin D1 and the histological grades of HCC was analyzed. RESULTS: CCND1 gene amplification was detected in 30% of the cases HCC. An overexpression of cyclin D1 mRNA and protein could be demonstrated in 45% and 70% cases respectively. The expression of cyclin D1 mRNA correlated with its gene amplification status (P < 0.05) and was responsible for the protein expression level (P < 0.05). There was a close relationship between the expression level of cyclin D1 protein and HCC histological grades (P < 0.05). CONCLUSIONS: CCND1 gene amplification is a common phenomenon in HCC and may be directly responsible for the cyclin D1 mRNA and protein overexpression. Cyclin D1 protein expression level is directly related to HCC histological grades. Therefore, CCND1 amplification and cyclin D1 overexpression may play an important role in development and differentiation of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Ciclina D1/genética , Amplificação de Genes , Neoplasias Hepáticas/genética , Adulto , Idoso , Ciclina D1/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Mensageiro/análise
11.
Zhonghua Bing Li Xue Za Zhi ; 32(3): 230-3, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12882688

RESUMO

OBJECTIVE: To investigate further the possible mechanism of carcinogenesis and portal invasion of hepatocellular carcinoma (HCC). METHODS: Samples of the primary tumors, cancer cells emboli in the portal veins and normal liver tissues adjacent to the tumor were collected from 20 cases of primary HCC. Expression of TIMP-3 (tissue inhibitor of metalloproteinases-3) protein was detected using Western blot. Expression of TIMP-3 mRNA was detected by RT-PCR. Methylation of TIMP-3 gene promoter was detected using methylation-specific PCR (MSP). RESULTS: Expression of TIMP-3 protein and mRNA were obtained in all of the normal liver tissues adjacent to tumor. However, loss of TIMP-3 protein expression was found in 5 and 36 cases respectively in the primary tumors and tumor cell emboli in portal veins. Expression of TIMP-3 protein and mRNA in primary tumors and tumor emboli were significantly lower than that in the normal liver tissues. Promoter methylation of TIMP-3 gene could be detected in primary tumors (7 cases) and cancerous emboli (9 cases) in HCC, while no methylation found in normal liver tissues. In all the HCC cases with promoter gene methylation including primary tumors and cancerous emboli in portal veins, 13 cases showed complete loss and 6 cases showed low expression of TIMP-3 protein and mRNA. Promoter methylation of TIMP-3 was noticed not related with the histological grading of HCC. CONCLUSIONS: There is a close relationship between loss or low expressions of TIMP-3 and carcinogenesis and portal invasion of HCC. The loss and low expression of TIMP-3 gene and protein were caused by methylation of the gene promoter.


Assuntos
Carcinoma Hepatocelular/genética , Metilação de DNA , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , Inibidor Tecidual de Metaloproteinase-3/genética , Adulto , Idoso , Western Blotting , Carcinoma Hepatocelular/química , Ilhas de CpG , Feminino , Humanos , Neoplasias Hepáticas/química , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-3/análise
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