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Fluorinated Polyimide/POSS Hybrid Polymers with High Solubility and Low Dielectric Constant 被引量:12
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作者 汪称意 Wen-tao Chen +2 位作者 Chang Xu 赵晓燕 Jian Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第11期1363-1372,共10页
A series of fluorinated polyimide/POSS hybrid polymers(FPI-4-FPI-16) were prepared via a facile synthetic route using 2,2'-bis(trifluoromethyl)benzidine, 4,4'-oxydiphthalic dianhydride and monofunctional POSS as... A series of fluorinated polyimide/POSS hybrid polymers(FPI-4-FPI-16) were prepared via a facile synthetic route using 2,2'-bis(trifluoromethyl)benzidine, 4,4'-oxydiphthalic dianhydride and monofunctional POSS as starting materials. The hybrid polymers showed excellent solubility and film formation ability. Flexible and robust hybrid films could be conveniently obtained via solution-casting. The hybrid films demonstrated low dielectric constants and high thermal stability. Their dielectric constants were in the range of 2.47-2.92 at 1 MHz measured for their capacitance, and were tunable and decreased with an increase of POSS content. Their 10% weight loss temperatures were in the range of 539-591 ℃ and the weight residual at 800 ℃ ranged from 48% to 53% in nitrogen atmosphere. These hybrid films also possessed good mechanical properties and hydrophobic characteristics. This work could provide a potential strategy for the preparation of fluorinated polyimide/POSS hybrid polymers. 展开更多
关键词 dielectric facile tunable solubility hydrophobic starting ranged conveniently capacitance constants
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Carbon and nitrogen allocations in corn grown in Central and Northeast China: different responses to fertilization treatments 被引量:3
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作者 MIAO Hui-tian Lü Jia-long +4 位作者 XU Ming-gang ZHANG Wen-ju HUANG Shao-min PENG Chang CHEN Li-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第6期1212-1221,共10页
In order to reveal the impact of various fertilization strategies on carbon(C) and nitrogen(N) accumulation and allocation in corn(Zea mays L.), corn was grown in the fields where continuous fertilization manage... In order to reveal the impact of various fertilization strategies on carbon(C) and nitrogen(N) accumulation and allocation in corn(Zea mays L.), corn was grown in the fields where continuous fertilization management had been lasted about 18 years at two sites located in Central and Northeast China(Zhengzhou and Gongzhuling), and biomass C and N contents in different organs of corn at harvest were analyzed. The fertilization treatments included non-fertilizer(control), chemical fertilizers of either nitrogen(N), or nitrogen and phosphorus(NP), or phosphorus and potassium(PK), or nitrogen, phosphorus and potassium(NPK), NPK plus manure(NPKM), 150% of the NPKM(1.5NPKM), and NPK plus straw(NPKS). The results showed that accumulated C in aboveground ranged from 2 550–5 630 kg ha^–1 in the control treatment to 9 300–9 610 kg ha^–1 in the NPKM treatment, of which 57–67% and 43–50% were allocated in the non-grain organs, respectively. Accumulated N in aboveground ranged from 44.8–55.2 kg ha^-1 in the control treatment to 211–222 kg ha^–1 in the NPKM treatment, of which 35–48% and 33–44% were allocated in the non-grain parts, respectively. C allocated to stem and leaf for the PK treatment was 65 and 49% higher than that for the NPKM treatment at the both sites, respectively, while N allocated to the organs for the PK treatment was 18 and 6% higher than that for the NPKM treatment, respectively. This study demonstrated that responses of C and N allocation in corn to fertilization strategies were different, and C allocation was more sensitive to fertilization treatments than N allocation in the area. 展开更多
关键词 fertilization allocation Northeast phosphorus fertilizers potassium organs ranged accumulated allocated
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The Influence of Key Environmental Variables on Phytoplankton Community Structure in the Estuary of Tidal Rivers Around Luoyuan Bay,China 被引量:4
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作者 PAN Wenbin ZHENG Peng +1 位作者 LIANG Yunyan CAI Yuanbin 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第5期803-813,共11页
A total of 348 species belonging to 8 phyla and 125 genera were observed in seasonally sampled phytoplankton of tidal rivers from 13 sampling sites around Luoyuan Bay, and all field samplings were carried out in produ... A total of 348 species belonging to 8 phyla and 125 genera were observed in seasonally sampled phytoplankton of tidal rivers from 13 sampling sites around Luoyuan Bay, and all field samplings were carried out in productive period(March/June/August/December) at ebb tide. Bacillariophyta species were the most abundant species, followed by Chlorophyta, Cyanophytes, Euglenophyta, Cryptophyta, Dinophyta, Xanthophyta and Chrysophytas. Seasonal distribution index(SDI) value ranged from 0.63 to 0.86, which meant that species found at those sites in 4 seasons tended to be largely different. Phytoplankton individuals ranged from 5.939×10~4 ind L^(-1) in winter to 75.31×10~4 ind L^(-1) in autumn. Phytoplankton biomass ranged from 0.620 mg L^(-1) in summer to 2.373 mg L^(-1) in autumn. The grey correlation analysis(GCA) showed that the nutrient variables played an important role in the influence on phytoplankton community in every season. The canonical correspondence analysis(CCA) revealed impact of environmental variables on the different species, most of Bacillariophyta species were negative correlation with nutrients(TP and NH_3-N) in the four seasons, Chlorophyta species and Cyanophyta species did not show obvious correlation with environment variables in every season. The combination of GRA analysis and CCA analysis provided a method to quantitatively reveal the correlation between phytoplankton community and environmental variables in water body of tidal rivers at this region. 展开更多
关键词 phytoplankton Cyanophyta season genera correspondence tidal autumn nutrients ranged canonical
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Genetic Diversity Analysis of Rice Germplasm in Tripura State of Northeast India Using Drought and Blast Linked Markers 被引量:2
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作者 Alpana ANUPAM Jahangir IMAM +4 位作者 Syed Mohammad QUATADAH Anantha SIDDAIAH Shankar Prasad DAS Mukund VARIAR Nimai Prasad MANDAL 《Rice science》 SCIE CSCD 2017年第1期10-20,共11页
We genotyped 74 rice germplasms including Tripura's local landraces, improved varieties, cultivars and breeding lines and other rice varieties using molecular markers for genetic diversity, drought QTLs, and blast re... We genotyped 74 rice germplasms including Tripura's local landraces, improved varieties, cultivars and breeding lines and other rice varieties using molecular markers for genetic diversity, drought QTLs, and blast resistance genes. The number of alleles per locus ranged from 2 to 5 with an average of 2.9. The polymorphic information content value per locus ranged from 0.059(RM537) to 0.755(RM252) with an average of 0.475. Cluster analysis based on 30 simple sequence repeat markers revealed 5 clusters and also indicated the presence of variability within the rice accessions. The drought QTL q DTY2.1 was found in 56.0% of germplasms and q DTY1.1 was detected in only 6.8% of the germplasms. Out of seven rice blast resistance genes screened, only two rice varieties, RCPL-1-82 and Buh Vubuk(Lubuk), were positive for four blast resistance genes while only Releng possessed two blast resistance genes. Among 74 rice germplasms, only three accessions, Releng, RCPL1-82 and Buh Vubuk(Lubuk), possessed both drought-related QTLs and blast resistance genes. Overall, the 74 indigenous rice genotypes showed low level of genetic diversity, which is in contrast to high level of genetic diversity among rice varieties in northeast India, where highlights the good farming practice, conservation of germplasms and the limitation of molecular markers employed in this study. The presence of both drought related QTLs and blast resistance genes in some of the germplasms can be useful in future breeding programmes. 展开更多
关键词 drought blast alleles breeding ranged polymorphic Northeast screened upland germplasm
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Microsatellite analysis of genetic diversity and population structure of freshwater mussel(Lamprotula leai) 被引量:2
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作者 Jin-Jin MIN Rong-Hui YE +1 位作者 Gen-Fang ZHANG Rong-Quan ZHENG 《Zoological Research》 CAS CSCD 2015年第1期34-40,共7页
Lamprotula leai is one of the most commercially important freshwater pearl mussels in China, but there is limited data on its genetic diversity and population structure. In the present study, 119 individuals from four... Lamprotula leai is one of the most commercially important freshwater pearl mussels in China, but there is limited data on its genetic diversity and population structure. In the present study, 119 individuals from four major geographical populations were investigated using 15 microsatellite loci identified via cross-species amplification. A total of 114 alleles were detected, with an average of 7.6 alleles per locus(range: 2 to 21). Among the four stocks, those from Hung-tse Lake and Poyang Lake had the lowest(0.412) and highest(0.455) observed heterozygosity respectively. The polymorphism information content(PIC) ranged from 0.374 to 0.927(mean: 0.907). AMOVA showed that 12.56% and 44.68% genetic variances were among populations and within individuals, respectively. Pairwise Fst ranged from 0.073 to 0.146, indicating medium genetic differentiation among the populations. In aggregate, our results suggest that inbreeding is a crucial factor accounting for deviations from Hardy–Weinberg equilibrium at 12 loci. Moreover, the genetic distance among four stocks ranged from 0.192 to 0.890. Poyang Lake and Hung-tse Lake were clustered together, joined with Dongting Lake and Anqing Lake. Given that specimens from Hungtse Lake showed the highest average allele richness, expected heterozygosity and PIC, this location may be the source of the highest quality germplasm resources and the stock from this area may be the best for future breeding efforts. 展开更多
关键词 alleles populations microsatellite heterozygosity freshwater ranged breeding stocks AMOVA germplasm
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Comparison of phytotoxicity of copper and nickel in soils with different Chinese plant species 被引量:1
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作者 LI Bo LIU Ji-fang +2 位作者 YANG Jun-xing MA Yi-bing CHEN Shi-bao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第6期1192-1201,共10页
Ecological risk assessment of metals in soils is important to develop the critical loads of metals in soils. Phytotoxicity is one of the endpoints for ecological risk assessment of soils contaminated with metals. The ... Ecological risk assessment of metals in soils is important to develop the critical loads of metals in soils. Phytotoxicity is one of the endpoints for ecological risk assessment of soils contaminated with metals. The sensitivity of eight Chinese plant species(bok choy, mustard, tomato, green chilli, paddy rice, barley, spinach and celery) to copper(Cu) and nickel(Ni) toxicity in two Chinese soils was investigated to assess their potential use for ecological risk assessment in the region. The results showed that bok choy and mustard were the two most sensitive species to Cu and Ni toxicities. Assessment of metal accumulation by the plants demonstrated that bok choy shoot had the highest bioconcentration factor(BCF, the ratio of metal concentration in plant shoots to metal concentration in soil). Given the importance of bok choy to agricultural production in Asia, it is therefore important that these sensitive plant species are included in species sensitivity distributions for ecological risk assessment of Cu and Ni in soils. 展开更多
关键词 paddy shoot nickel tomato contaminated toxicity agricultural vegetative displayed ranged
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Analysis of the forest fires in the Antalya region of Turkey using the Keetch–Byram drought index 被引量:1
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作者 Tugrul Varol Mertol Ertugrul 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期811-819,共9页
We investigated the correlation of large fires([300 ha) from 1992 to 2013 within the borders of the Antalya Regional Directorate of Forestry using the Keetch–Byram drought index(KBDI). Daily KBDI values were calc... We investigated the correlation of large fires([300 ha) from 1992 to 2013 within the borders of the Antalya Regional Directorate of Forestry using the Keetch–Byram drought index(KBDI). Daily KBDI values were calculated for each year, and values for the period before the year 2000 differed significantly from those after2000. After 2000(large fires occurred in 2004, 2006, 2007,2008, 2010, and 2013), when KBDI values increased, the KBDI, but not the number of fires, was inversely correlated with the natural log of the burned area(NLBA). While there were both high and low KBDI values when the NLBA was small, only high KBDI values were associated with high NLBA values. Particularly for logarithmic values of 4 and higher, KBDI values increased in parallel with increases in NLBA values. On the basis of a Mann–Whitney U test done in addition to a Pearson correlation test, we found that when the burned areas were grouped according to small and large areas, the KBDI could be used to distinguish the two groups. Using a conditional probability analysis, we found that 4th, 5th and 6th class KBDI values may lead to large fires at the 60 % possibility.Similarly, the possibility of large fires greater than the median burned area in any given 6 years was found to be48 %. In addition, while the mean value of KBDI is 390.51 for the period from May to September for these 6 years, it is 359.93 for the other years. Consequently, the area burned also increased as the KBDI classes(Class 0: 0–99, Class 1:100–199, Class 2: 200–299, Class 3: 300–399, Class 4:400–499, Class 5: 500–599, Class 6: 600–699, and Class 7:700–800) increase. 展开更多
关键词 drought grouped possibility distinguish median Turkey conditional explained moisture ranged
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Advanced Glycation Endproducts in 35 Types of Seafood Products Consumed in Eastern China 被引量:2
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作者 WANG Jing LI Zhenxing +4 位作者 PAVASE Ramesh Tushar LIN Hong ZOU Long WEN Jie LV Liangtao 《Journal of Ocean University of China》 SCIE CAS 2016年第4期690-696,共7页
Advanced glycation endproducts(AGEs) have been recognized as hazards in processed foods that can induce chronic diseases such as cardiovascular disease, diabetes, and diabetic nephropathy. In this study, we investigat... Advanced glycation endproducts(AGEs) have been recognized as hazards in processed foods that can induce chronic diseases such as cardiovascular disease, diabetes, and diabetic nephropathy. In this study, we investigated the AGEs contents of 35 types of industrial seafood products that are consumed frequently in eastern China. Total fluorescent AGEs level and Nε-carboxymethyl-lysine(CML) content were evaluated by fluorescence spectrophotometry and gas chromatography-mass spectrometry(GC-MS), respectively. The level of total fluorescent AGEs in seafood samples ranged from 39.37 to 1178.3 AU, and was higher in canned and packaged instant aquatic products that were processed at high temperatures. The CML content in seafood samples ranged from 44.8 to 439.1 mg per kg dried sample, and was higher in roasted seafood samples. The total fluorescent AGEs and CML content increased when seafood underwent high-temperature processing, but did not show an obvious correlation. The present study suggested that commonly consumed seafood contains different levels of AGEs, and the seafood processed at high temperatures always displays a high level of either AGEs or CML. 展开更多
关键词 glycation AGEs carboxymethyl processed instant lysine ranged dried aquatic consumed
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Elemental Concentrations in Biological Samples of Coronavirus Disease (COVID-19) and Other Pulmonary Disease Patients
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作者 Hassan Imran Afridi Tasneem Gul Kazi +4 位作者 Farah Naz Talpur Jameel Ahmed Baig Ghulam Qadir Chanihoon Ayaz Lashari Ghulam Mustafa Channa 《American Journal of Analytical Chemistry》 2021年第5期162-187,共26页
<strong>Background:</strong> Recently, Coronavirus Disease 2019 (COVID-19) has been affected by the extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has developed important global health a... <strong>Background:</strong> Recently, Coronavirus Disease 2019 (COVID-19) has been affected by the extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has developed important global health anxiety. At this time, the treatment options for this disease are only moderately successful. Smoking has been related to COVID-19 and its mortality, and it has the potential to affect bacteriological and viral conversion, clinical effects, and treatment outcomes. <strong>Methods:</strong> The aim of this study was to determine the relationship between critical essential trace {zinc (Zn), iron (Fe), and copper (Cu)} and toxic {cadmium (Cd) and nickel (Ni)} elements in human biological samples such as scalp hair, serum, saliva, blood, nasal fluid, and sputum of smoking and nonsmoking male COVID-19 patients (n = 139, age range 25 - 38 years) from Hyderabad, Pakistan. For comparative purposes, the biological specimens of referent persons (n = 83), pulmonary Tuberculosis (T.B) patients (n = 67), Pneumonia (n = 56) of the same age groups were also be analyzed. Microwave oven mediated digestion method was employed, and digestion of samples was carried out with the help of 2:1 mixture solution of HNO<sub>3</sub> (65%) and H<sub>2</sub>O<sub>2</sub> (30%). Atomic absorption spectrometry was employed for the determination of elemental concentrations from the microwave oven employed digested samples. <strong>Results:</strong> The found average of essential elements (Zn, Fe, and Cu) in biological specimens of smoker and nonsmoker male COVID-19, T.B, and Pneumonia patients was found to lower, whilst cadmium and nickel were found to be higher when compared with samples from referents (p < 0.001). <strong>Conclusions:</strong> Improved elemental (Cu, Fe, Zn) concentrations may also decrease the risk of bacterial co-infection by enhancing the mucociliary clearance and respiratory epithelial barrier function, in addition to providing direct antibacterial effects against <i>S. pneumoniae</i>. Our findings also suggest that higher 展开更多
关键词 COVID-19 Other Lung Infected Diseases Essential Trace Elements Toxic Elements Biological Samples Age ranged 25 - 38 Years
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Test of Small RNA Sequencing Repeatability in Rice
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作者 SUN Hong-zheng PENG Ting +3 位作者 ZHANG Jing LI Jun-zhou DU Yan-xiu ZHAO Quan-zhi 《Rice science》 SCIE CSCD 2017年第1期56-60,共5页
Deep sequencing of small RNAs(sR NA) is widely used in sR NAs studies in plants. In order to investigate the sequencing frequency variation of sR NAs, the same sR NA samples from rice grains were sequenced twice usi... Deep sequencing of small RNAs(sR NA) is widely used in sR NAs studies in plants. In order to investigate the sequencing frequency variation of sR NAs, the same sR NA samples from rice grains were sequenced twice using deep sequencing technique. The sR NAs were classified into three categories, high abundance(〉 100 RPM), medium abundance(10–100 RPM) and low abundance(1–10 RPM). According to the repeat sequencing data of the same sample, highly expressed sR NAs(〉 100 RPM) were less subject to random drift, and 95% of the sR NAs Log2 ratio between two samples fell between-0.649 and 0.558. The same trend was observed in mediumly expressed sR NAs(10–100 RPM), and 95% of the Log2 ratio fell between-0.535 and 0.759. As to lowly expressed sR NAs(1–10 RPM), 95% of the Log2 ratio varied between-1.009 and 1.011. These results can be used as a theoretical guide to find differentially expressed s RNAs in sR NA studies in plants. 展开更多
关键词 sequencing Sequencing abundance sequenced varied drift ranged fitted removing RNA
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Isolation and Characterization of Nine Microsatellite Markers for Red-backed Ratsnake,Elaphe rufodorsata
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作者 Tianlong FU Shan SUN +1 位作者 Chaonan ZHU Yanfu QU 《Asian Herpetological Research》 SCIE CSCD 2016年第3期227-228,共2页
The red-backed ratsnake(Elaphe rufodorsata) is widely distributed in East Asia, especially China. This species is a common snake in plain river network region. In the past several decades, E. rufodorsata has dramati... The red-backed ratsnake(Elaphe rufodorsata) is widely distributed in East Asia, especially China. This species is a common snake in plain river network region. In the past several decades, E. rufodorsata has dramatically declined due to the effect of human activities and over hunting for traditional Chinese medicine. We developed nine species-specific microsatellite loci in 190 individuals collected from Huzhou, Zhejiang province in China. These markers revealed a high degree of genetic diversity(13–41 alleles per locus) and heterozygosity(H O ranged from 0.266 to 0.941, and H E ranged from 0.851 to 0.937). No locus exhibited significant deviations from Hardy–Weinberg equilibrium. There was no evidence of linkage disequilibrium among pairs of loci. These microsatellite markers were described in our study will be valuable tools for the long term management and population-level studies(e.g. the population structure, genetic diversity and variation, individual paternity and evolutionary history) of the species. 展开更多
关键词 microsatellite alleles backed heterozygosity linkage locus ranged snake declined evolutionary
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In vitro Biological Evaluation of Graphene on Neuronal Cells
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作者 易继凌 赵政 +2 位作者 LI Shipu YIN Yixia WANG Xinyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第4期925-930,共6页
We prepared graphene(GE) with a mean size of 3087 nm.The transition of graphene oxide(GO) to GE was confirmed by UV-visible spectroscopy,Fourier transform infrared spectroscopy(FTIR) and X-ray diffraction(XRD)... We prepared graphene(GE) with a mean size of 3087 nm.The transition of graphene oxide(GO) to GE was confirmed by UV-visible spectroscopy,Fourier transform infrared spectroscopy(FTIR) and X-ray diffraction(XRD).The experimental results of optical microscopic observation indicated that the GE ranged from 5 to 20 μg/mL did not affect the cell morphologies of the PC12 cells.The results of cell viability and membrane integrity assay supported that of optical microscopic observation and demonstrated that the GE ranged from 5 to 20 μg/mL presented no obvious cytotoxicity.However,reactive oxygen species(ROS) assay suggested that an elevation of ROS level could be detected when the GE ranged from 20 to 100 μg/mL.These results showed that the GE ranged from 5 to 10 μg/mL presented an excellent in vitro biocompatibility and was one kind of potential biomaterials for neural tissue engineering. 展开更多
关键词 ranged visible microscopic integrity suspensions elevation agglomeration purity cytotoxicity sputtering
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Evaluation of Brazilian wild Hevea germplasm for cold tolerance:genetic variability in the early mature growth
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作者 G.Prabhakara Rao P.C.Kole 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期755-765,共11页
Hevea brasiliensis is a commercially cultivated species for its natural rubber(NR) latex in South East Asian countries. To meet the ever-increasing demand, NR cultivation has been extended to non-traditional regions... Hevea brasiliensis is a commercially cultivated species for its natural rubber(NR) latex in South East Asian countries. To meet the ever-increasing demand, NR cultivation has been extended to non-traditional regions due to the limited scope of further expansion in traditional rubbergrowing areas in India. These areas are often confronted with various abiotic stresses, especially high and low temperatures, which cause reduction in plant growth, thereby increasing its uneconomical immaturity period. Eighteen wild Hevea accessions along with two modern clones RRII203 and PB 235 and two check clones RRIM 600 and Haiken 1 were evaluated in the early mature growth phase.The site was at Nagrakata, West Bengal, the sub-Himalayan cold-prone region of India. In Hevea, crop production is governed by two major factors, growth-vigor and production capacity. Growth-vigor is of special importance because the production of rubber is a process linked with the early growth of the plant, which results in early tappability and early economic gains. The genotypes exhibited highly significant clonal differences(P = 0.05) for all the growth traits. Tappability percentage in the seventh year, ranged from 0.33 %(AC 3074, AC 3075, AC 3293) to 89.67 %(RO 2727). The most vigorously growing accession(RO2727) reached tappabile girth early in the seventh year when the girth of plant ranged from 22.38 cm(AC 3293) to53.12 cm(RO 2727). The general mean was 43.32 cm, and the similar growth trend was exhibited by these accessions in the tenth year also. Annual girth increment(cm a-1) over3 years ranged from 1.81 cm(AC 3075) to 6.80 cm(RO2727). The mean winter girth increment(cm a-1) over4 years ranged from 0.13 cm(AC 3075) to 0.96 cm(RO2727) as compared to the check clone RRIM 600(1.11 cm)and Haiken 1(1.10 cm). Wide differences between the phenotypic coefficient of variation(50.29) and genotypic coefficient of variation(24.82) were observed for winter girth increment. Girth in the 展开更多
关键词 Hevea germplasm mature cultivated phenotypic ranged abiotic rubber accession breeding
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Formation of Uniform Oil-Soluble Fe_3O_4 Nanoparticles via Oil-Water Interface System 被引量:1
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作者 薛精诚 王会 +2 位作者 郑学双 吴瑛 周兴平 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期175-179,共5页
Nowadays,the novel oil water interface method has attracted a considerable attention owing to the advantages of mild reaction conditions,simple operation,low cost,and high efficiency.In this paper,uniform oil-soluble ... Nowadays,the novel oil water interface method has attracted a considerable attention owing to the advantages of mild reaction conditions,simple operation,low cost,and high efficiency.In this paper,uniform oil-soluble Fe_3O_4 nanoparticles(NPs) were synthesized by oil-water interface method from mixing iron tristearate of 0.067mol/L in cyclohexane with ferrous sulfate in water.The as-prepared products were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),vibrating sample magnetometer(VSM),Fourier transform infrared spectroscopy(FT-IR) and thermogravimetric analyzer(TGA).TEM images and XRD profiles showed that the size of the oil-soluble products ranged in 1.7-6.9 nm.VSM indicated that the Fe_3O_4 NPs were superparamagetic.FT-IR and TGA proved that oleic acid was combined to the surface of Fe_3O_4 NPs closely.TEM images and XRD profiles revealed that the most suitable reaction concentration of NH_3·H_2O,oleic acid/water in volume,reaction temperature and reaction time were 4.5 mol/L,50:1 000,80℃ and 6 h,respectively.The formation mechanism of the nearly monodispersed Fe_3O_4 NPs was that the preformed Fe_3O_4 nuclei were capped by oleic acid as early as the nucleation occurred in oil-water interface and subsequently entered into oil phase to stop growing. 展开更多
关键词 oleic Uniform magnetometer vibrating nucleation surfactant microemulsion mixing ranged ferrous
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An Approach to Determination of Phenolic Compounds in Seawater using SPME-GC-MS Based on SWCNTs Coating 被引量:1
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作者 ZHU Jia WANG Ying ZENG Lin 《Journal of Ocean University of China》 SCIE CAS 2016年第4期655-659,共5页
Phenolic compounds have become one kind of the important pollutants of the marine environment. Single-walled Carbon nanotubes, as one-dimensional nano materials, have light weight and perfect hexagonal structure of co... Phenolic compounds have become one kind of the important pollutants of the marine environment. Single-walled Carbon nanotubes, as one-dimensional nano materials, have light weight and perfect hexagonal structure of connections, with many unusual mechanical, chemical and electrical properties. In recent years, with the research of carbon nanotubes and other nano materials, the application prospect is also constantly discussed. In this paper, homemade single-walled carbon nanotubes(SWCNTs) coating was used for establishing an analytical approach to the determination of five kinds of phenolic compounds in seawater using SPME-GC-MS. Optimal conditions: After saturation was conducted with Na Cl, and p H was adjusted to 2.0 with H_2SO_4, the extract was immersed in a water bath at 40 for GC℃-MS determination through 40-min agitating extraction at 500 rmin^(-1) and 3-min desorption at 280℃. The liniearities ranged between 0.01-100 μg L^(-1), and the determination limits ranged between 1.5-10 ngL^(-1). The relative standard deviation(RSD, n = 5) was less than 6.5%. For the phenolic compounds obtained from the spiked recovery test for actual seawater samples, the rates of recovery were 87.5%-101.7%, and the RSDs were less than 8.8%, which met the requirements of determination. Due to its simplicity, high efficiency and low consumption, this approach is suitable for the analysis of trace amounts of phenolic compounds in marine waters. 展开更多
关键词 SWCNTs nanotubes walled hexagonal SPME ranged simplicity immersed seawater establishing
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CLINICAL OBSERVATIONS ON 278 CASES OF CERVICAL SPONDYLOPATHY TREATED WITH ELECTRO ACUPUNCTURE AND MASSOTHERAPY 被引量:1
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作者 骆仲达 骆竞洪 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1997年第2期116-118,共3页
From Dec. 1990 to Dec. 1993, 278 cases of cervical spondylopathy were treated with electroacupuncture and massotherapy. The cure rate was 82.7%; but in the control group, it was only 61%, indicating that electroacupun... From Dec. 1990 to Dec. 1993, 278 cases of cervical spondylopathy were treated with electroacupuncture and massotherapy. The cure rate was 82.7%; but in the control group, it was only 61%, indicating that electroacupuncture may enhance the cure rate (P【 0.05). Of the 278 cases treated by three to five sessions, the pain and numbness disappeared in about 96% of the patients. 展开更多
关键词 VERTEBRAL recurrence NEURALGIA SHOULDER CURATIVE severity relieve DISAPPEARANCE ranged eliminated
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Effects of Periodical Salinity Fluctuation on the Growth, Molting, Energy Homeostasis and Molting-Related Gene Expression of Litopenaeus vannamei 被引量:1
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作者 ZHANG Dan GUO Xiantao +1 位作者 WANG Fang DONG Shuanglin 《Journal of Ocean University of China》 SCIE CAS 2016年第5期911-917,共7页
To determine the response of Litopenaeus vannamei to periodical salinity fluctuation, a 30-day experiment was conducted in laboratory. In this experiment, two salinity fluctuation amplitudes of 4(group S4) and 10(grou... To determine the response of Litopenaeus vannamei to periodical salinity fluctuation, a 30-day experiment was conducted in laboratory. In this experiment, two salinity fluctuation amplitudes of 4(group S4) and 10(group S10) were designed. The constant salinity of 30(group S0) was used as the control. Levels of shrimp growth, molting frequency(MF), cellular energy status(ATP, ADP and AMP), as well as the expression of genes encoding molt-inhibiting hormone(MIH), crustacean hyperglycemic hormone(CHH), ecdysteroid-regulated protein(ERP), and energy-related AMP-activated protein kinase(AMPK) were determined. The results showed that periodical salinity fluctuation significantly influenced all indicators except MF which ranged from 13.3% in group S10 to15.4% in group S4. In comparison with shrimps cultured at the constant salinity of 30, those in group S4 showed a significant elevation in growth rate, food conversion efficiency, cellular energy status, ERP and MIH gene transcript abundance, and a significant reduction in CHH and AMPK transcript abundance(P < 0.05). However, salinity fluctuation of 10 only resulted in a significant variation in MIH and CHH gene expression when compared to the control(P < 0.05). According to our findings, L. vannamei may be highly capable of tolerating salinity fluctuation. When ambient salinity fluctuated at approx. 4, the increased MF and energy stores in organisms may aid to promoting shrimp growth. 展开更多
关键词 salinity shrimp fluctuation transcript periodical AMPK ranged Molting abundance Periodical
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CLINICAL OBSERVATIONS ON TREATMENT OF HYPERPROLACTINEMIA BY ACUPUNCTURE
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作者 刘继章 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1994年第2期121-122,共2页
In the last three years the author hastreated 8 cases of idiopathic hyper-prolactinemia by acupuncture with satisfac-tory results.Presented in this paper is a re-port of clinical observations in the cases sotreated.
关键词 ACUPUNCTURE STERILITY ACUPUNCTURE SECRETION ranged recurrence inhibited REMAINING reinforcing minutes
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THERAPEUTIC EFFECT IN 216 CASES OF ACNE,CHLOASMA,AND FLAT CONDYLOMA TREATED WITH MOULD-LIKE MASKS CONTAINING CHINESE DRUGS
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作者 李秀敏 陈雅茹 +2 位作者 赵丽平 李映琳 李兆美 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1992年第4期259-262,共4页
Application of mould-like masks is oneof the external therapies recently used in thetreatment of common face-marring skindiseases.From December 1988 to June1989,our department treated 216 cases ofache,chloasma and fla... Application of mould-like masks is oneof the external therapies recently used in thetreatment of common face-marring skindiseases.From December 1988 to June1989,our department treated 216 cases ofache,chloasma and flat condyloma by ap-plying respectively ache-removing,patch-dispelling,and wart-ehminatingmasks we made up by combining variousChinese drugs,and obtained fairly good re-sults.The work is reported as follows. 展开更多
关键词 CONDYLOMA fairly removing patch MOULD plying department RADIX ranged removed
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A preliminary study on P53gene in lung cacertissues of worers exposed to siticn and welding fumes
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《China Medical Abstracts(Internal Medicine)》 1997年第3期133-134,共2页
关键词 preliminary EXPOSED WELDING MUTATION SUPPRESSOR deter finding PREVALENCE latter ranged
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