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1.
Rare Metals ; 40(8): 2017-2025, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679100

RESUMO

Owing to their high performance and earth abundance, copper sulfides (Cu2-x S) have attracted wide attention as a promising medium-temperature thermoelectric material. Nanostructure and grain-boundary engineering are explored to tune the electrical transport and phonon scattering of Cu2-x S based on the liquid-like copper ion. Here multiscale architecture-engineered Cu2-x S are fabricated by a room-temperature wet chemical synthesis combining mechanical mixing and spark plasma sintering. The observed electrical conductivity in the multiscale architecture-engineered Cu2-x S is four times as much as that of the Cu2-x S sample at 800 K, which is attributed to the potential energy filtering effect at the new grain boundaries. Moreover, the multiscale architecture in the sintered Cu2-x S increases phonon scattering and results in a reduced lattice thermal conductivity of 0.2 W·m-1·K-1 and figure of merit (zT) of 1.0 at 800 K. Such a zT value is one of the record values in copper sulfide produced by chemical synthesis. These results suggest that the introduction of nanostructure and formation of new interface are effective strategies for the enhancement of thermoelectric material properties. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s12598-020-01698-6) contains supplementary material, which is available to authorized users.

2.
Mol Cell Probes ; 34: 68-70, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28552829

RESUMO

In this study, 17 male-specific amplified fragment length polymorphism (AFLP) markers were identified between male and female Humulus scandens plants. BLAST analysis revealed that 7 of the 17 sex-linked sequences were highly similar to retrotransposons. Two stable male-specific sequence-characterized amplified regions (SCAR) markers were developed. These AFLP and SCAR markers are novel molecular probes that can be used efficiently to identify the genetic gender of H. scandens and may provide a basis for further investigations on the evolution of sex chromosomes.


Assuntos
Genes de Plantas/genética , Marcadores Genéticos/genética , Humulus/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos
3.
J Hazard Mater ; 155(1-2): 58-64, 2008 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-18166267

RESUMO

Synthesis of pure-form zeolite A were investigated using four concentrations of NaOH solution to dissolve Si source form fly ash, and with the addition of Al source, to prepare initial gel. Experimental results demonstrated, for two-stage method, that NaOH concentrations in initial gel played an important role in synthesis of pure-form zeolite A using fly ash as raw materials. Generally, pure-form zeolite A could be synthesized when following conditions were used: NaOH concentrations, 1.67, 5 and 6.67 M; the synthesis temperature, 100 degrees C; the corresponding crystallization time, 340, 250 and 190 min. However, a mixture phases of zeolites A and X were obtained at the condition of 3.33 M NaOH solution during various crystallization times. It was found that the higher NaOH concentration was used, the shorter crystallization time of zeolite A was required and the narrower particle size distribution of zeolite A was achieved. In addition, zeolite A submicron-crystals were first synthesized from fly ash using two-stage method in our study.


Assuntos
Carbono/química , Conservação dos Recursos Naturais/métodos , Material Particulado/química , Hidróxido de Sódio/química , Gerenciamento de Resíduos/métodos , Zeolitas/química , Cinza de Carvão , Cristalização , Resíduos Industriais , Tamanho da Partícula
4.
J Hazard Mater ; 151(2-3): 306-15, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17662522

RESUMO

Bactericide wastewater (BIW) contains isothiazolin-ones, high salinity, toxicity and non-biodegradable organic concentrations. In order to enhance biodegradable capacity, chemical coagulation and electrochemical oxidation were applied to pretreatment processes. FeSO(4).7H2O, pH 12 and 20 mmol/l were determined as optimal chemical coagulation condition; and 15 mA/cm2 of current density, 10 ml/min of flow rate and pH 7 were chosen for the most efficient electrochemical oxidation condition at combined treatment. The wastewater which consisted mainly of isothiazolin-ones and sulfide was efficiently treated by chemical coagulation and electrochemical oxidation. The optimal pretreatment processes showed 60.9% of chemical oxygen demand (COD), 99.5% of S(2-) and 96.0% of isothiazolin-ones removal efficiency. A biological treatment system using membrane bioreactor (MBR) adding powder-activated carbon (PAC) was also investigated. COD of the wastewater which was disposed using a MBR was lower than 100 mg/l.


Assuntos
Antibacterianos/análise , Eletroquímica/métodos , Oxigênio/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Reatores Biológicos , Carbono/química , Eletrólitos , Desenho de Equipamento , Concentração de Íons de Hidrogênio , Modelos Químicos , Compostos Orgânicos/análise , Oxigênio/metabolismo , Temperatura , Tiazóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 42(8): 592-5, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19115624

RESUMO

OBJECTIVE: To understand the epidemiological features of viral hepatitis, and provide scientific evidence for developing strategies for prevention and control. METHODS: Through descriptive epidemiological methodology, the epidemiological characteristics of 1121 viral hepatitis cases in Chongwen District (1997-2006) were studied. chi2-test was used in ratio comparison. RESULTS: There were 1121 viral hepatitis cases occurring in the past decade, and the incidence rate was declining by year with the average of 27.10/ 100,000. Of which, the incidence rate of viral hepatitis B was the highest (13.90/ 100,000), viral hepatitis C (1.38/100,000) was the lowest. The proportion of viral hepatitis B was the highest (575, 51.29%) and viral hepatitis C (57, 5.08%) was the lowest. The incidence of viral hepatitis A, B and no-typing was declining year by year, while viral hepatitis C and E was climbing. Most viral hepatitis A and E cases occurred in Spring and Winter, and the difference of incidence rate between male and female was observed (chi2 = 188.39, P < 0.001). The findings also showed that viral hepatitis might occur in all kind of occupation, but most were workers (306, 27.3%) and officers (209, 18.64%). For the age distribution, 20 -49 years old group took the majority (749, 66.82%); and for the transmission route, blood transfusion (7.64/ 100,000) was significantly higher than fecal-oral route (3.02/ 100,000) (chi2 = 5.09, P < 0.01). CONCLUSION: It is necessary to raise and increase the public awareness for viral hepatitis prevention and control, and enhance immunization. Moreover, effective measures should be taken to the safety of blood and blood products, and to prevent nosocomial infection.


Assuntos
Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/prevenção & controle , Adolescente , Adulto , China/epidemiologia , Feminino , Hepatite A/epidemiologia , Hepatite A/prevenção & controle , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
6.
Zhonghua Bing Li Xue Za Zhi ; 36(11): 730-5, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-18307875

RESUMO

OBJECTIVE: To study the clinicopathologic features and prognostic factors of Chinese patients with mantle cell lymphoma. METHODS: One hundred and two cases of mantle cell lymphoma occurring in Chinese patients were studied by light microscopy and immunohistochemistry. The follow-up information was also analyzed. The cases were classified as mantle zone, nodular or diffuse patterns and as typical or blastoid variants. Age, Ann-Arbor staging, B symptoms, hematologic parameters, histologic variants, mitotic index and immunophenotype were assessed for possible prognostic implication. RESULTS: The median age of the patients was 59 years (range: 30 to 79 years) and the male-to-female ratio was 2.92:1. Seventy-one patients (87.65%) presented with advanced stage disease (Ann Arbor stage III to IV). B symptoms were present in 45.45% of patients. The commonest site of involvement was lymph node (100%). The other involved sites included bone marrow (64.44%), spleen (63.16%), Waldeyer's ring (31.25%), peripheral blood (29.41%), liver (22.64%) and gastrointestinal tract (14.71%). All cases expressed B-cell markers but were negative for T-cell marker. Majority of cases were positive for cyclin D1 (94.12%) and CD5 (71.43%). Blastoid variant accounted for 24.51% of cases. Amongst the 68 cases with follow-up data available, the median survival was 10 months. Parameters associated with shorter survival included diffuse pattern, blastoid variant, high mitotic index, high proliferative activity and presence of bone marrow involvement. CONCLUSIONS: The clinicopathologic features and prognostic factors of mantle cell lymphoma occurring in Chinese are similar to those in Caucasians. Diffuse pattern, blastoid variant, high mitotic index, high proliferative activity and involvement of bone marrow indicate poor prognosis.


Assuntos
Ciclina D1/metabolismo , Linfoma de Célula do Manto/patologia , Adulto , Idoso , Antígenos CD20/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígenos CD5/metabolismo , Antígenos CD79/metabolismo , Terapia Combinada , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Seguimentos , Humanos , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/terapia , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Prognóstico , Vincristina/uso terapêutico
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(4): 777-80, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17608197

RESUMO

Magnetic photocatalysts (TiO2/Fe3O4), which are liable to be separated and recovered, were prepared using Fe3O4 as the support. The surface morphology and crystal pattern were investigated by means of XRD, SEM, XPS and FTIR. The results showed that TiO2 wraps on the surface of Fe3O4. The photocatalytic activity of the catalysts was investigated by photocatalytic decolorization of (TNR). The photocatalytic activity of the catalysts is high and the separating ratio is good.

8.
J Environ Sci (China) ; 18(3): 562-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17294657

RESUMO

TiO2 sol was prepared by sol-gel technique with tetrabutyl titanate as precursor. Supported TiO2 catalysts on activated carbon were prepared by soak and sintering method. The aggregation of nano-TiO2 particles can be effectively suppressed by added polyethylene glycol (PEG) as a surface modifier. The average particle diameter of TiO2, specific surface area and absorbability of catalyst can be modified. Based on characteristics of the TiO2 photocatalyst with XRD, specific surface area, adsorption valves of methylene blue and the amount of TiO2 supported on the activated carbon, the photocatalytic degradation of L-acid was studied. The effect of the factors, such as pH of the solution, the initial concentration of L-acid on the photocatalytic degradation of L-acid, were studied also. It was found that when the pH of the solution is 1.95, the amount of photocatalyst is 0.5 g, the concentration of the L-acid solution is 1.34 x 10(-3) mol/L and the illumination time is 7 h, the photocatalytic degradation efficiency of L-acid can reach 89.88%. The catalyst was reused 6 times and its degradation efficiency hardly changed.


Assuntos
Carvão Vegetal/química , Naftalenossulfonatos/química , Fotoquímica/métodos , Titânio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Catálise , Concentração de Íons de Hidrogênio , Naftalenossulfonatos/análise , Oxigênio/análise , Tamanho da Partícula , Transição de Fase , Polietilenoglicóis , Difração de Raios X
9.
Huan Jing Ke Xue ; 37(12): 4891-4898, 2016 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965333

RESUMO

Size fractionation and chemical composition of municipal solid waste incinerator (MSWI) fly ash were investigated. And the leaching efficiency of heavy metals was contrastively studied using toxicity characteristic leaching procedure (TCLP), European standard protocol (EN12457-2), sequential extraction procedure (SEP) and physiologically based extraction test (PBET) for different size-fractionated fly ash. The results indicated that the main compositing elements of fly ash were Ca, Si, Al, Mg, Fe, Na, K. 58.7% of fly ash particles were in the range of 38-106 µm and the amount in the<150 µm particle-size fraction accounted for more than 90% of in total, Cu, Pb and Cd mainly existed in the residual form with a minor amount of exchange fraction for any size-fractioned fly ash particles. TCLP result showed that leaching amounts of Zn, Cu and Pb, except for As and V, firstly increased and then decreased with the reduction of particle size. The leaching amount of Zn reached the highest value of 547 mg·kg-1 in the range of 38-106 µm, whereas the leaching amount of heavy metals exhibited a lower level for all size-fractioned fly ash particles. The extraction concentrations of Zn, Pb, Cu and As reached 3270, 339, 335 and 16.8 mg·kg-1 for the PBET tests, respectively, which were significantly higher than those of the TCLP. Therefore, heavy metals in MSWI fly ash had the potential bioavailability to human body.


Assuntos
Cinza de Carvão/toxicidade , Incineração , Metais Pesados/toxicidade , Resíduos Sólidos , Disponibilidade Biológica , Tamanho da Partícula , Material Particulado , Eliminação de Resíduos
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(3): 563-5, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12953542

RESUMO

The present paper analysed in detail the reasons for the errors found in the literature when Boltzmann plot was used for the temperature measurement of a high-density plasma produced by electrothermal capillary discharge. The reliability of experiment can reach as high as 98%-99.5% and the error is only +/- 6.5% when the spectroscopic parameters, such as transition probability A, statistical weight of upper level g, and the energy of upper level Ei, are selected correctly for the temperature measurement of a high-density plasma produced by electrothermal capillary discharge by Boltzmann plot in atomic emission spectroscopy.

11.
Huan Jing Ke Xue ; 35(3): 1009-15, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24881390

RESUMO

The effects of biosurfactant alkyl polyglycosides (APG) on the hydrolysis and acidification of waste activited sludge including dosage of APG and hydrolysis time were investigated. It was found that APG reduced the tension of sludge hydrolysate, promoting sludge hydrolysis. The concentrations of SCOD, protein and soluble carbonhydrate reached the maximum within 12 h at the optimal dosage of 0.2 g x g(-1) TSS, rising from 4 280.2, 1 122.9 and 246.5 mg x L(-1) to 6481.1, 1 639.3 and 1205.8 mg x L(-1), respectively, and the short-chain fatty acids (SCFAs) concentration increased from 1309.9 mg x L(-1) to 2221.6 mg x L(-1) simultaneously, the percentage of individual SCFA changed as well, and the time required to reach the maximal SCFAs concentration will be prolonged with the increase of dosage. With increasing APG dosage, a-glucosidase relative enzyme activities increased from 1.5 to 2.5, while protease relative enzyme activity increased from 1.4 to 1.9 at low dosages and decreased to 1.5 at high dosages. Regardless of the biosurfactant APG, alpha-glucosidase and protease enzyme activities decreased along with the hydrolysis time. The pH showed a tendency of first decreasing and then increasing.


Assuntos
Ácidos Graxos Voláteis/química , Glicosídeos/química , Esgotos/química , Concentração de Íons de Hidrogênio , Hidrólise
12.
Virol Sin ; 25(2): 107-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20960307

RESUMO

Herpes simplex virus type 1 (HSV-1) is a commonly occurring human pathogen worldwide. There is an urgent need to discover and develop new alternative agents for the management of HSV-1 infection. Tripterygium hypoglaucum (level) Hutch (Celastraceae) is a traditional Chinese medicine plant with many pharmacological activities such as anti-inflammation, anti-tumor and antifertility. The usual medicinal part is the roots which contain about a 1% yield of alkaloids. A crude total alkaloids extract was prepared from the roots of T. hypoglaucum amd its antiviral activity against HSV-1 in Vero cells was evaluated by cytopathic effect (CPE) assay, plaque reduction assay and by RT-PCR analysis. The alkaloids extract presented low cytotoxicity (CC(50) = 46.6 µg/mL) and potent CPE inhibition activity, the 50% inhibitory concentration (IC(50)) was 6.5 µg/mL, noticeably lower than that of Acyclovir (15.4 µg /mL). Plaque formation was significantly reduced by the alkaloids extract at concentrations of 6.25 µg/mL to 12.5 µg/mL, the plaque reduction ratio reached 55% to 75 which was 35% higher than that of Acyclovir at the same concentration. RT-PCR analysis showed that, the transcription of two important delayed early genes UL30 and UL39, and a late gene US6 of HSV-1 genome all were suppressed by the alkaloids extract, the expression inhibiting efficacy compared to the control was 74.6% (UL30), 70.9% (UL39) and 62.6% (US6) respectively at the working concentration of 12.5 µg/mL. The above results suggest a potent anti-HSV-1 activity of the alkaloids extract in vitro.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antivirais/isolamento & purificação , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Tripterygium/química , Alcaloides/toxicidade , Animais , Antivirais/toxicidade , Chlorocebus aethiops , Efeito Citopatogênico Viral/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Concentração Inibidora 50 , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Transcrição Gênica/efeitos dos fármacos , Ensaio de Placa Viral , Proteínas Virais/biossíntese
13.
Huan Jing Ke Xue ; 28(8): 1746-51, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17926404

RESUMO

The photocatalyst of Mo(6+) doped TiO2 was prepared by a sol-gel method and immobilized to granular activated carbon by coating. The photodegradation of 1-naphthol-5-sulphonic acid (L-acid), and the effects of the loading numbers of the photocatalyst on activated carbon and the light sources on the removal efficiency of L-acid and TOC of solution were investigated. The experimental results show that the Mo(6+) doping can help TiO2 to extend the active scope to the visible-light region. The doped TiO2 supported on activated carbon is anatase with the average particle diameter 17.8 nm. It has been found that the activity of catalyst is reduced with its loading number, and the Mo(6+) doping does not affect the catalyst activity in the ultraviolet region and adsorption of L-acid. The removal efficiency of L-acid and TOC of solution is 57% and 53% respectively when 0.4 g doped photocatalyst is applied in 100 mg x L(-1) L-acid solution illuminated by visible light for 4 hours, while it is 13% and 10% respectively in the case of the undoped photocatalyst. The catalyst can be reused for 4 times to keep the degradation efficiency hardly changed.


Assuntos
Carvão Vegetal/química , Luz , Molibdênio/química , Titânio/química , Adsorção , Catálise/efeitos da radiação , Naftalenossulfonatos/química , Fotoquímica , Fotólise/efeitos da radiação , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
14.
Fen Zi Xi Bao Sheng Wu Xue Bao ; 39(3): 281-4, 2006 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16944605

RESUMO

Sex-linked molecular markers are being obtained, which would be essential to be used in the screening of different sex of dioecious plants at the seedling stage. Furthermore, it is important in cloning the gene related to the sex. In this study the random amplified polymorphic DNA (RAPD) technique was employed with the objective to find markers linked to sex determination in Asparagus. A total of 100 primers were tested with the same PCR cycling procedure. A female-associated fragment with a length of about 867bp was generated with S12 primer. The fragment was cloned and sequenced, showing it is abundant in AT and contains 2 shorter open reading frames. In order to convert the RAPD marker into SCAR (sequence characterized amplified regions) marker, 24bp specific primers were constructed and used for PCR amplifying. The female-linked dominant SCAR marker was obtained, which would be efficient to identify the different sex of Asparagus officinalis L.


Assuntos
Asparagus/genética , Marcadores Genéticos/genética , Análise para Determinação do Sexo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Feminino , Dados de Sequência Molecular , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
15.
Huan Jing Ke Xue ; 26(3): 126-9, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-16124484

RESUMO

The preparation of nanoscale oxide/polyvinylidene fluoride (PVDF) composite hollow fiber membrane by phase transition process was introduced. The effects of nanoscale titania and alumina particles on structure and property of composite hollow fiber membrane were investigated. The separation property, microstructure and crystalline phase of composite membranes were characterized by bovine serum albumin (BSA) rejection experiment, scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), respectively. The results show that the properties of composite membrane are improved greatly compared to the pure PVDF membranes. The BSA rejection ratios of pure PVDF, Al2O3/PVDF and TiO2/PVDF membranes were 3.27%, 67.20% and 86.67%, respectively. The pure water fluxes of Al2O3/PVDF and TiO2/PVDF membranes were 2.3 and 2.6 times higher than that of pure PVDF membranes. Moreover, the pore size and its distribution of composite membrane characterized by nitrogen isothermal absorption measurement are smaller and narrower than pure PVDF membranes.


Assuntos
Óxido de Alumínio/química , Nanotubos , Polivinil/química , Titânio/química , Membranas Artificiais , Tamanho da Partícula , Espectrofotometria , Propriedades de Superfície
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