Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Hazard Mater ; 203-204: 118-27, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22209325

RESUMO

The feasibility of using Indian Jujuba Seeds (IJS) (Zizyphus maruritiana), abundantly available in and around the Nallamalla forest in Andhra Pradesh, for the anionic dye (Congo red, CR) adsorption from aqueous solution, has been investigated as low cost and eco-friendly adsorbent. Adsorption studies were conducted on a batch process, to study the effects of contact time, initial concentration of CR, pH and temperature. Maximum colour removal was observed at pH 2. The equilibrium data was analyzed by the Langmuir, the Freundlich and the General isotherms. The data fitted well with the Langmuir model, with a maximum adsorption capacity of 55.56 mg g(-1). The pseudo-second-order kinetics was the best for the adsorption of CR, by IJS (Z. maruritiana) with good correlation. Thermodynamic parameters, such as standard free energy change (ΔG°), standard enthalpy change (ΔH°) and standard entropy change (ΔS°), were analyzed. The results suggest that IJS (Z. maruritiana) is a potential low-cost adsorbent for the CR dye removal from synthetic dye wastewater.


Assuntos
Vermelho Congo/isolamento & purificação , Resíduos Industriais , Sementes/metabolismo , Ziziphus/embriologia , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Termodinâmica
2.
Rev. bras. plantas med ; 12(2): 188-194, abr.-jun. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-578953

RESUMO

Ziziphus joazeiro Mart. é uma arvore brasileira endêmica da Caatinga e tem diversos usos no Nordeste. As sementes apresentam dormência tegumentar e o presente trabalho teve por objetivo avaliar tratamentos pré-germinativos com ácido sulfúrico concentrado para superar a dormência. O delineamento experimental utilizado foi o inteiramente casualizado, com 9 tratamentos, sendo 0, 30, 60, 90, 120, 150, 180, 210 e 240 minutos de imersão em ácido sulfúrico concentrado P.A. com três repetições de 50 sementes, em dois experimentos. No experimento 1 foram usadas sementes recém coletadas e a avaliação foi feita durante 140 dias. No experimento 2 foram usadas sementes armazenadas por 5 meses e a avaliação feita durante 100 dias. Ziziphus joazeiro apresenta dormência imposta pelo endocarpo que envolve as sementes, e é necessário o uso de ácido sulfúrico durante 180 minutos para sementes recém-coletadas e por 240 ou 270 minutos, para sementes armazenadas por 5 meses para se atingir 80 por cento de emergência. O tempo de armazenamento das sementes pode influenciar a resposta germinativa, com emergência mais rápida após o armazenamento por 5 meses.


Ziziphus joazeiro Mart. is a Brazilian tree endemic to Caatinga and has been largely used in the Northeast of Brazil. Its seeds present tegument dormancy and this work aimed to evaluate pre-germinative treatments with concentrated sulfuric acid to break dormancy. Experimental design was completely randomized, with 9 treatments, i.e. 0, 30, 60, 90, 120, 150, 180, 210, and 240 min of immersion in concentrated sulfuric acid A.R. with three replicates of 50 seeds, in two experiments. In experiment 1, newly collected seeds were evaluated for 140 days. In experiment 2, 5-month stored seeds were evaluated for 100 days. Ziziphus joazeiro presents dormancy imposed by the endocarp that involves the seeds, and sulfuric acid should be used for 180 min on newly collected seeds and for 240 or 270 min on 5-month stored seeds in order to reach 80 percent emergence. Seed storage time may influence the germinative response, with faster emergence after 5-month storage.


Assuntos
Germinação , Epiderme Vegetal , Fenômenos Químicos/métodos , Ácidos Sulfúricos , Tratamento Térmico/métodos , Ziziphus/embriologia , Etnobotânica , Sementes/crescimento & desenvolvimento
3.
Sex Plant Reprod ; 22(2): 73-85, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20033458

RESUMO

Floral development of the synchronous dichogamous species Ziziphus mauritiana, as followed by light and scanning electron microscopy (SEM), was divided into 11 stages using a series of landmark events. Main cellular events happen synchronously in the female and the male structures, such as meiosis in micro- and macrosporocyte cells, tetrad microspore formation and appearance of the functional megaspore cell, and onset of embryo sac differentiation coinciding with mitosis in the microspores. The last stage was characterized by anthesis and continued development of the flower, beginning with anther dehiscence (male phase) and proceeding to the female phase, which was characterized by style elongation. Flowers exhibit synchronous protandrous dichogamy; anthesis takes place in the morning (group A, e.g., clone Q-29) and afternoon (group B, e.g., clone B5/4). Stigma receptivity started after the male phase and occurred synchronously and complementarily with pollen dispersal in the two clones. Pollen viability and production were similar in the two clones, but the pollen diameter of Q-29 was significantly larger than that of B5/4. This study provides the basis for understanding the biological mechanisms regulating floral development, thus expanding the prospects for Z. mauritiana breeding programs and for further molecular and genetic studies of this species.


Assuntos
Flores/crescimento & desenvolvimento , Ziziphus/crescimento & desenvolvimento , Flores/embriologia , Flores/ultraestrutura , Microscopia Eletrônica de Varredura , Óvulo Vegetal/embriologia , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/ultraestrutura , Pólen/embriologia , Pólen/crescimento & desenvolvimento , Pólen/ultraestrutura , Ziziphus/embriologia , Ziziphus/ultraestrutura
4.
Fen Zi Xi Bao Sheng Wu Xue Bao ; 39(5): 423-30, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17117552

RESUMO

The results of embryological observation on embryo development in the thirteen cultivars of jujube indicated that they shared the same experience from proembryo to globular embryo, heart-shaped embryo, torpedo-shaped embryo and cotyledon stage embryo. Embryo began aborting from globular or heart-shaped embryo period in most of cultivars of jujube, but in few of them embryo could keep synchronous developing to cotyledon stage embryo. And the courses of embryo development were not synchronous.


Assuntos
Sementes/anatomia & histologia , Sementes/embriologia , Ziziphus/embriologia
5.
J Chromatogr Sci ; 41(1): 41-3, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12597596

RESUMO

A simple and fast capillary gas chromatographic (CGC) method with flame ionization detection is developed for the analysis of fatty oil in Semen Ziziphi Spinosae. After methyl-esterification, eight components are identified by gas chromatography-mass spectrometry. The derivatization condition is investigated in order to validate this method. Palmitic acid and stearic acid are quantitated simultaneously. The limits of detection are 5.024 microg/mL for palmitic acid and 6.957 microg/mL for stearic acid, respectively. The limits of quantitation are 16.76 microg/mL for palmitic acid and 23.19 microg/mL for stearic acid, respectively. The percent recoveries of palmitic and stearic acid are 97.4% and 96.6%. CGC is shown to be a quick and informative tool for the analysis of fatty oil in Semen Ziziphi Spinosae.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Óleos de Plantas/análise , Sementes/química , Ziziphus/embriologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...