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61.
The effects of various experimental parameters on adsorption of Zn2+ metal ion from its aqueous solution by castor seed hull and also by activated carbon have been investigated using batch adsorption experiments. It has been found that the amount of zinc adsorbed per unit mass of the hull increases with the initial metal ion concentration, contact time, solution pH and with the amount of the adsorbent. Kinetic experiments clearly indicate that adsorption of zinc on both castor hull and activated carbon is a three-step process??a rapid adsorption of the metal ion, a transition phase, and an almost flat plateau. This has also been confirmed by the intraparticle diffusion model. It has also been found that the zinc adsorption process followed pseudo-second order kinetics. The kinetic parameters including rate constants have been determined at different initial metal ion concentration, pH, amount, and type of adsorbent, respectively. The Langmuir and Freundlich adsorption isotherm models have been used to interpret the equilibrium adsorption data. The Langmuir model yields better correlation coefficients. The monolayer adsorption capacities (q m ) of castor hull and activated carbon have been compared with those for others reported in the literature. The value of separation factor (R L ) derived from the Langmuir model gives an indication of favorable adsorption. Finally, from comparative studies, it has been found that castor hull is a potentially attractive adsorbent as compared to commercial activated carbon for the removal of zinc from aqueus effluents.  相似文献   
62.
Abstract

Thirty-four sugar beet drought-tolerant half-sib families were screened in greenhouse experiment under saline (16?dSm?1) and normal conditions, and a subset of 10 tolerant genotypes were selected for evaluating of yield-related traits, Na+, K+, and α-amino-N nitrogen contents under saline field condition (12?dSm?1). Drought-tolerant genotypes showed a different tolerance level under salt stress. Significant correlation was observed between EP2s and STIEP2 in greenhouse with root yield (RY) in saline field condition. It should be possible that a simple measurement at 16?dSm?1 in the greenhouse can be used as main part of sugar beet salt-tolerant breeding program. In total, genotypes SBSI-DR I-HSF14-P.23 (# 16) and 436B-HSF9-P.27 (# 26) were recognized as salt- and drought-tolerant genotypes with low Na+ and K+ contents in root and high white sugar content (WSC) and RY in field. A larger panel of genotypes to validate this kind of association is necessary.  相似文献   
63.
This work examines the effects of two deficit irrigation strategies, conventional deficit irrigation (DI) and partial root-zone drying (PRD), on mature navel orange trees. The study carried out during two consecutive years (2008 and 2009) in a semi-arid climate on a silty–clay–loam soil in the north of Iran. Both DI and PRD trees were irrigated at two levels, 75 and 50% (DI75, PRD75, DI50 and PRD50) of the full irrigation (FI). In DI, irrigation water was applied to both sides of the tree rows, similar to FI. In PRD, irrigation water was applied alternately to only one side, at each irrigation event. Results showed that DI treatments reduced fruit yield by ~30% compared with FI, but PRD treatments caused no reduction in fruit yield. No negative impact was detected in fruit quality after applying DI and PRD treatments. Shoot growth decreased in all DI and PRD treatments in both years. In DI, stomatal resistance was higher (50%) than in FI, but it was not significantly affected in PRD. The irrigation water use efficiency of PRD trees increased to nearly twice that of FI. According to these two years' results, we recommend PRD as an acceptable deficit irrigation strategy in the region.  相似文献   
64.
Fish Physiology and Biochemistry - In a feeding experiment, cottonseed meal (CSM) was used to replace fishmeal (FM) in the diet of snubnose pompano, Trachinotus blochii, supplemented with lysine...  相似文献   
65.
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type.  相似文献   
66.
ABSTRACT

Salinity and preferred nutrient composition of Chaetoceros affinis and Skeletonema costatum were tested. Salinity was tested at 12, 16, 23, 28, and 32 ppt. Three compositions of nitrogen (N), phosphorus (P), and potassium (K) and two on-farm low-cost alternative media sources, cow urine (CU) and hatchery waste water (HWW), were tested to find the suitable NPK ratio and to determine the efficacy of the on-farm media respectively. Chaetoceros affinis preferred 23 ppt salinity, while Skeletonema costatum preferred both 28 and 32 ppt. Among the NPK treatments, higher cell density was observed in 4:1:1 followed by 4:2:1 ratios. Significant differences in maximum cell density of both species were observed in the NPK treatments while only S. costatum showed significant difference in CU and HWW.  相似文献   
67.
The J wave has never been documented in the electrocardiogram (ECG) of cats presenting with hypertrophic cardiomyopathy (HCM). The present study aimed to describe the presence, morphology, amplitude, and duration of J waves in cats with HCM. It included 20 apparently healthy cats and 45 cats diagnosed with HCM based on clinical, echocardiographic, ECG, and radiographic examination. The cats were of different breeds (Persian: 40, domestic short hair: 21, Siamese: 4), ages (6.01 ± 4.34 years), sexes (male: 33, female: 32), and weights (3.30 ± 1.51 kg). The J wave was absent in the ECGs of the healthy population, but was detected in 29 out of 45 cats with HCM (63%). The J waves were observed at the QRS-ST junction in more than one limb lead of the ECG. Only positive deflections with an amplitude ≥0.05 mV were included, as measured by an ECG ruler in three consecutive heart cycles. The J waves were mainly present in leads II (n=20) and III (n=16), with amplitudes of 0.06 ± 0.02 and 0.08 ± 0.03 mV; their mean (± SD) duration was 0.16 ± 0.05 msec in lead II and 0.18 ± 0.05 msec in lead III. They occurred in both notched and slurred morphologies, with the latter being more common. In conclusion, J waves were a common finding in the ECGs of cats with HCM.  相似文献   
68.
69.
The self-incompatible cultivar ‘Dashehari’ has a tendency to bear a very poor crop on the south-east to south-west sides of the tree. The panicles emerge rather early in the season (December–January) when they are usually damaged by frost. Their blooming period does not coincide with the other cultivars.Two years' observations have revealed that a single de-blossoming treatment, at budburst stage, results in a highly significant increase in yield compared to the control. The incidence of floral malformation, which is usually very high in the early panicles, was substantially reduced by this treatment.  相似文献   
70.
Soaking of bulbs in 3 concentrations of indoleacetic acid (IAA), gibberellic acid (GA3), 2-chloroethyltrimethyl ammonium chloride (cycocel) or 2-chloroethylphosphonic acid (ethrel) showed various responses on growth and flowering. IAA increased the weight and number of bulblets, GA3 increased bulb weight. Cycocel (1000 mg l?1) increased the number of flowers, while GA3 increased the diameter of the flowers.Application of IAA at 100 mg l?1 and GA3 at 10, 100 or 1000 mg l?1 twice as foliar spray at an interval of 30 days promoted the number of bulblets on the treated plants, while high concentrations of cycocel and ethrel (1000 mg l?1) increased the weight of bulblets. All concentrations of IAA, GA3 and 1000 mg l?1 cycocel increased the number and size of the flowers.  相似文献   
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