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81.
Fast pyrolysis of soybean cake: product yields and compositions   总被引:1,自引:0,他引:1  
This study was an investigation of the role of important parameters influencing pyrolysis yields from soybean cake. Experiments were carried out at temperatures ranging from 400 to 700 degrees C, for various nitrogen flow rates, heating rates and particle sizes. The maximum liquid yield was 42.83% at a pyrolysis temperature of 550 degrees C with a sweeping gas rate of 200 cm3 min(-1) and heating rate of 700 degrees C min(-1) for a soybean cake sample having 0.425 < D(p) < 0.85 mm particle size. The various characteristics of liquid product were identified. Thus, the aliphatic sub-fraction of the bio-oil was analysed by GC-MS and further structural analyses of bio-oil and aromatic and polar sub-fractions were conducted using FT-IR and 1H-NMR. The H/C ratios and the structural analysis of the fractions obtained from the biocrudes showed that the fractions were quite similar to currently utilised transport fuels.  相似文献   
82.
Substituted polyaniline/chitosan(PANIs/Ch) composites were chemically synthesized by using ammonium peroxydisulfate as oxidant and characterized by measurements of conductivity, FTIR, UV–vis, SEM and TGA techniques. FTIR spectra of the composites revealed that there is a strong interaction between substituted polyanilines and chitosan. Among the substituted polyaniline/chitosan composites synthesized, poly(N-ethylaniline)/chitosan PNEANI/Ch has the highest conductivity with a value of 1.68 × 10?4 S/cm. The P2EANI/Ch composite exhibited higher thermal stability than the other composites. SEM images of the composites showed an agglomerated granular morphology of substituted polyaniline particles coated on the surface of chitosan.  相似文献   
83.
A collection of 96 female Turkish fig (Ficus carica L.) accessions was studied to elucidate genetic structure and estimate diversity and genetic similarity distribution among the female figs present in Turkish genetic resources, using 157 molecular genome markers including 129 sequence-related amplified polymorphisms, 21 random amplified polymorphic DNAs, and 7 simple-sequence repeats. The plant samples mainly included Turkish fig collections selected throughout the country over the course of a half-century. Neighbor-joining analysis revealed continuous dissimilarity range, and it was difficult to classify figs into distinct groups. The principle component analysis produced similar results. The analysis of molecular variance indicated that 95 and 93% of genetic variation were explained by within geographic origins and similar fruit rind color, respectively. Sub-structuring Bayesian analysis assigned the 96 female figs into four sub-populations, and indicated that they were highly related. The corrected allelic pairwise distances among the six geographic origins were less than 5%. This study suggests that geography- and color-based groups were not genetically distinct among the Turkish figs.  相似文献   
84.
85.
Aromatic (Bas-370, PB-1) and non-aromatic (Pusa-677, Pusa-834) rice were selected for the characterization and for distribution of lipoxygenase (Lox) genes. Polymorphism was observed when genomic DNA of rice varieties was hybridized with a heterologous lipoxygenase probe. A distinct polymorphic fragment (approximately 1.2 kb) was found in Bas-370. Sub-genomic library of Bas-370 was constructed and screened with LoxA probe. The smallest putative clone (pBas-14) of approximately 1.2 kb was sequenced. Complete nucleotide and deduced amino acid sequence showed the clone was 1134 bp long and comprised of 378 amino acid residues. PCR amplification of genomic DNA from four rice varieties with a soybean Lox primer also showed a polymorphic fragment of size approximately 600 bp (amplicon) in aromatic varieties that was sequenced directly. Nucleotide sequence alignment between pBas-14 and amplicon concluded that the amplicon was a part of the insert pBas-14.  相似文献   
86.
87.
Methyl esters substituted at position with good leaving groups (nucleofugals) are smoothly hydrolysed by Pig Liver Esterase (PLE) in moderate to high yields.  相似文献   
88.
The synthesis of porcine plasma kallikrein (pPK) segment (11–23), of sequence Phe-Phe-Arg-Gly-Gly-Asp-Val-Ser-Ala-Met-Tyr-Thr-Pro, present in the first tandem repeat sequence of the regulatory chain of PK, has been accomplished following the peptide fragments (5 + 4 + 4) condensation strategy in solution, as well as by fluorenylmethoxycarbonyl solid-phase chemistry. This and another synthetic PK segment of residues (328–343) present in the fourth tandem repeat sequence [Cys(ACM)-Ser-Leu-Arg-Leu-Ser-Thr-Asp-Gly-Ser-Pro-Thr-Arg-Ile-Thr-Tyr] and synthesized by a solid-phase method, were fully characterized by 1H nuclear magnetic resonance, fast atom bombardment mass spectrometry, amino acid composition and reversed-phase high-performance liquid chromatography. Proteolysis of these peptides by either rat PK (rPK) or trypsin resulted in cleavages between Arg↓Gly for pPK (11–23) and between Arg↓Leu and Arg↓Ile for rPK (328–343). Kinetic studies revealed that for peptide pPK (11–23), the catalytic efficiency (kcat/Km) of rPK is 9-fold higher than that of trypsin, but for the other peptide, rPK (328–343), kcat/Km of trypsin is 49-fold higher than that of rPK. The facile cleavage of pPK (11–23) by rPK confirms the Arg13↓Gly14 position as the site of autolytic degradation of PK and also explains its special preference for Phe-Phe-Arg sequence.  相似文献   
89.
90.
Refugees are at high risk of developing mental disorders. There is no evidence from randomized controlled trials (RCTs) that psychological interventions can prevent the onset of mental disorders in this group. We assessed the effectiveness of a self‐help psychological intervention developed by the World Health Organization, called Self‐Help Plus, in preventing the development of mental disorders among Syrian refugees experiencing psychological distress in Turkey. A two‐arm, assessor‐masked RCT was conducted in two Turkish areas. Eligible participants were adult Syrian refugees experiencing psychological distress (General Health Questionnaire ≥3), but without a diagnosis of mental disorder. They were randomly assigned either to the Self‐Help Plus arm (consisting of Self‐Help Plus combined with Enhanced Care as Usual, ECAU) or to ECAU only in a 1:1 ratio. Self‐Help Plus was delivered in a group format by two facilitators over five sessions. The primary outcome measure was the presence of any mental disorder assessed by the Mini International Neuropsychiatric Interview at six‐month follow‐up. Secondary outcome measures were the presence of mental disorders at post‐intervention, and psychological distress, symptoms of post‐traumatic stress disorder and depression, personally identified psychological outcomes, functional impairment, subjective well‐being, and quality of life at post‐intervention and six‐month follow‐up. Between October 1, 2018 and November 30, 2019, 1,186 refugees were assessed for inclusion. Five hundred forty‐four people were ineligible, and 642 participants were enrolled and randomly assigned to either Self‐Help Plus (N=322) or ECAU (N=320). Self‐Help Plus participants were significantly less likely to have any mental disorders at six‐month follow‐up compared to the ECAU group (21.69% vs. 40.73%; Cramer''s V = 0.205, p<0.001, risk ratio: 0.533, 95% CI: 0.408‐0.696). Analysis of secondary outcomes suggested that Self‐Help Plus was not effective immediately post‐intervention, but was associated with beneficial effects at six‐month follow‐up in terms of symptoms of depression, personally identified psychological outcomes, and quality of life. This is the first prevention RCT ever conducted among refugees experiencing psychological distress but without a mental disorder. Self‐Help Plus was found to be an effective strategy for preventing the onset of mental disorders. Based on these findings, this low‐intensity self‐help psychological intervention could be scaled up as a public health strategy to prevent mental disorders in refugee populations exposed to ongoing adversities.  相似文献   
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