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A new poly(vinylchloride) (PVC) membrane electrode for trace level determination of Co2+ ions has been developed based on 5-amino-3-methylisothiazole as an ionophore, o-nitrophenyloctylether as a plasticizer and oleic acid (OA) as a good lipophilic additive. The electrode exhibits a Nernstian slope of 29.5 ± 0.2 mV/decade in a linear range of 1.0 × 10−1 to 6.3 × 10−7 M for Co2+ ions. The detection limit of this electrode is 3.9 × 10−7 M. It has a fast response time of 12 s and can be used for a period of 4 months without any divergence in potentials. The proposed electrode reveals a good selectivity for Co (II) over a wide variety of other tested cations and could be used in the pH range 3.3–9.0. The electrode was successfully applied as an indicator electrode for the potentiometric titration of cobalt ions with EDTA as well as for the direct determination of Co (II) in real samples.  相似文献   
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The study evaluates the effect of ozone pretreatment on biodegradability enhancement of biomethanated distillery effluent. Results revealed that ozone pretreatment led to biodegradability index (BI = BOD/COD) enhancement up to 0.58 along with COD, color and toxicity reduction of up to 33%, 25% and 40%, respectively. Anaerobic digestion of pretreated effluent resulted in favorable biogas generation with methane content, yield and COD reduction of up to 62%, 39 mL/g COD and 57%, respectively. Kinetics of biogas generation determined by modified Gompertz model indicated methane production potential and production rate of 48.08 mL/g COD and 8.085 mL/g COD.day respectively under optimal conditions.  相似文献   
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Sign language fills the communication gap for people with hearing and speaking ailments. It includes both visual modalities, manual gestures consisting of movements of hands, and non-manual gestures incorporating body movements including head, facial expressions, eyes, shoulder shrugging, etc. Previously both gestures have been detected; identifying separately may have better accuracy, but much communicational information is lost. A proper sign language mechanism is needed to detect manual and non-manual gestures to convey the appropriate detailed message to others. Our novel proposed system contributes as Sign Language Action Transformer Network (SLATN), localizing hand, body, and facial gestures in video sequences. Here we are expending a Transformer-style structural design as a “base network” to extract features from a spatiotemporal domain. The model impulsively learns to track individual persons and their action context in multiple frames. Furthermore, a “head network” emphasizes hand movement and facial expression simultaneously, which is often crucial to understanding sign language, using its attention mechanism for creating tight bounding boxes around classified gestures. The model’s work is later compared with the traditional identification methods of activity recognition. It not only works faster but achieves better accuracy as well. The model achieves overall 82.66% testing accuracy with a very considerable performance of computation with 94.13 Giga-Floating Point Operations per Second (G-FLOPS). Another contribution is a newly created dataset of Pakistan Sign Language for Manual and Non-Manual (PkSLMNM) gestures.  相似文献   
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Copper (Cu) is an essential element involved in various metabolic processes in plants, but at concentrations above the threshold level, it becomes a potential stress factor. The effects of two different cytokinins, kinetin (KIN) and 6-benzylaminopurine (BAP), on chlorophyll a fluorescence parameters, stomatal responses and antioxidation mechanisms in castor (Ricinus communis L.) under Cu2+ toxicity was investigated. Ricinus communis plants were exposed to 80 and 160 μM CuSO4 added to the growth medium. Foliar spraying of 15 μM KIN and BAP was carried out on these seedlings. The application of these cytokinins enhanced the tissue water status, chlorophyll contents, stomatal opening and photosynthetic efficiency in the castor plants subjected to Cu2+ stress. The fluorescence parameters, such as Fm, Fv/Fo, Sm, photochemical and non-photochemical quantum yields, energy absorbed, energy trapped and electron transport per cross-sections, were more efficiently modulated by BAP application than KIN under Cu2+ toxicity. There was also effective alleviation of reactive oxygen species by enzymatic and non-enzymatic antioxidation systems, reducing the membrane lipid peroxidation, which brought about a relative enhancement in the membrane stability index. Of the various treatments, 80 µM CuSO4 + BAP recorded the highest increase in photosynthetic efficiency compared to other cytokinin treatments. Therefore, it can be concluded that BAP could effectively alleviate the detrimental effects of Cu2+toxicity in cotyledonary leaves of R. communis by effectively modulating stomatal responses and antioxidation mechanisms, thereby enhancing the photosynthetic apparatus’ functioning.  相似文献   
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The treatment of a complex pharmaceutical effluent using a combination of ozonation and biological treatment is reported with the use of ozonation as a pre- and posttreatment. Pretreatment facilitated biodegradability index (BI = BOD/COD) enhancement of up to 0.44 along with COD and color reduction of up to 42% and 33%, respectively. Subsequent anaerobic biodegradation of effluent indicated negligible biogas generation; however, aerobic biodegradation of pretreated effluent resulted in COD reduction (73%) and color reduction (62%), which was also indicated by the biokinetic parameters. Further, ozonation as a posttreatment led to higher overall COD (87%) and color (93%) removal.  相似文献   
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A range of olefin-containing polyesters were prepared by acyclic diene metathesis (ADMET) and were then subjected to cyclo-depolymerization (CDP). CDP involves metathesis of the 1,2-disubstituted olefinic linkages and gives a homologous family of strainless macrocyclic oligomers (MCOs). When Grubbs' “first generation” catalyst was used at 23 °C the CDPs were sluggish and required reaction times of several days, but with the “second generation” Grubbs' catalyst at 40 °C CDPs were complete in only 2-4 h. Macrocyclic olefin-containing lactones were also prepared by ring-closing metathesis. Under appropriate reaction conditions (i.e. neat cyclics or very concentrated solutions of cyclics) the strainless macrocycles successfully underwent ring-opening metathesis polymerizations (ROMPs). Unlike most ROMPs reported in the literature, which are usually enthalpically-driven, these ROMPs are entropically-driven (ED-ROMPs). The results obtained clearly demonstrate that 21-, 24-, 27-, 28-, 38-, 45-, 52-, 63-, 64-, 68- and 84-membered macrocycles polymerized successfully. Two of the ED-ROMPs were carried out in films. These ROMPs appeared to proceed in part in the solid phase, i.e. were examples of solid state polymerization.  相似文献   
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The study set out to investigate the relationship between physical functioning, inflammatory status, and sleep disturbance in a chronic hemodialysis (HD) population. Forty-six maintenance HD patients from the McGill University Health Centre were enrolled in this study between October 2005 and 2006. The well-validated Human Activity Profile (HAP) questionnaire and the RAND 36-item survey were used to assess physical functioning. Subjects were given the Pittsburgh Sleep Quality Index (PSQI) survey to evaluate the degree of sleep disturbance. Inflammatory status was assessed with the average value of serial C-reactive protein (CRP) levels for each patient, over a period of 12 months before their enrollment in the study. A multivariate logistic regression model was created for these analyses to control for potential confounders, including dialysis adequacy, inflammation, and hemoglobin. Seventy-six percent of the study population had poor sleep as per the Pittsburgh Sleep Quality Index (PSQI score > or = 5). In addition, 65% of subjects had high CRP values (>5 mg/L). On univariate analysis, both a CRP >5 mg/L and a lower adjusted activity score (AAS) on the HAP were significantly associated with poor sleep (PSQI score > or = 5). Multivariate logistic analysis demonstrated that the AAS remained significantly associated with poor sleep, with a 6% decrease in the odds of poor sleep for each score increase in the AAS of the HAP. Poor physical functioning in chronic HD patients, as measured by the HAP, is associated with sleep disturbance, after controlling for inflammation and dialysis adequacy.  相似文献   
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