An aerobic bacterium strain, F-3-4, capable of effectively degrading 2,6-di-tert-butylphenol(2,6-DTBP), was isolated and screened out from an acrylic fiber wastewater and the biofilm in the wastewater treatment facili...An aerobic bacterium strain, F-3-4, capable of effectively degrading 2,6-di-tert-butylphenol(2,6-DTBP), was isolated and screened out from an acrylic fiber wastewater and the biofilm in the wastewater treatment facilities. This strain was identified as Alcaligenes sp. through morphological, physiological and biochemical examinations. After cultivation, the strain was enhanced by 26.3% in its degradation capacity for 2,6-DTBP. Results indicated that the strain was able to utilize 2,6-DTBP, lysine, lactamine, citrate, n-utenedioic acid and malic acid as the sole carbon and energy source, alkalinize acetamide, asparagine, L-histidine, acetate, citrate and propionate, but failed to utilize glucose, D-fructose, D-seminose, D-xylose, serine and phenylalanine as the sole carbon and energy source. The optimal growth conditions were determined to be: temperature 37℃, pH 7.0, inoculum size 0.1% and shaker rotary speed 250 r/min. Under the optimal conditions, the degradation kinetics of 2,6-DTBP with an initial concentration of 100 mg/L was studied. Results indicated that 62.4% of 2,6-DTBP was removed after 11 d. The degradation kinetics could be expressed by Eckenfelder equation with a half life of 9.38 d. In addition, the initial concentration of 2,6-DTBP played an important role on the degradation ability of the strain. The maximum initial concentration of 2,6-DTBP was determined to be 200 mg/L. Above this level, the strain was overloaded and exhibited significant inhibition.展开更多
Stretchable electronics represents a direction of recent development in next-generation semiconductor devices.Such systems have the potential to offer the performance of conventional wafer-based technologies,but they ...Stretchable electronics represents a direction of recent development in next-generation semiconductor devices.Such systems have the potential to offer the performance of conventional wafer-based technologies,but they can be stretched like a rubber band,twisted like a rope, bent over a pencil,and folded like a piece of paper.Isolating the active devices from strains associated with such deformations is an important aspect of design.One strategy involves the shielding of the electronics from deformation of the substrate through insertion of a compliant adhesive layer. This paper establishes a simple,analytical model and validates the results by the finite element method.The results show that a relatively thick,compliant adhesive is effective to reduce the strain in the electronics,as is a relatively short film.展开更多
To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different anti...To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different antibody titers were challenged with a Nigerian isolate of virulent IBDV. Mortality rates of the different groups were plotted against their respective mean PHA antibody titers. A group with zero antibody titer had a mortality rate of 75% while those with PHA antibody titers of 185.6, 243.2, 256 and 307.2 had mortality rates of 40%, zero, zero and zero respectively. Linear equation generated for a line of best fit of the graph of mortality rates of the chicks on their IBD antibody titers gave antibody titer (X) at which mortality (Y) would be zero as 300. A mortality of 75% and the high antibody level needed to protect chicks suggest that the isolate may be a hypervirulent strain.展开更多
Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 ...Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 (a specific local strain in China) of MDV. Methods\ Two oligonucleotide primers were synthesized according to the reported sequence of \%meq\% gene an ideal oncogenic candidate and our previously determined sequence of BamHI L fragment of Marek′s disease herpesvirus (MDV), respectively. Reverse transcriptase PCR(RT PCR) assay was performed by using these primers and the mRNA as a template which was isolated from visceral lymphoblastoid tumors obtained from chickens artificially infected with strain Beijing 1 of oncogenic MDV. Southern blot molecular hybridization was further carried out to detect the product of RT PCR with digoxigenin labeled nucleotide probe from BamHI I2 and L fragment in the gene library of MDV strain GA, respectively. Results\ Two probes could simultaneously hybridize this cDNA amplified by RT PCR with a length of about 730 bp. Conclusion\ It is suggested that \%meq\% transcription could extend from the right hand end of BamHI I2 to the adjacent BamHI L, and the BamHI L region was likely to be transcribed in MDV induced lymphoblastoid tumors.展开更多
Mercury-resistant strain D2 was isolated from mercury-contaminated soil and investigations on its 16S rDNA sequence,growth,minimal inhibitory concentrations(MICs) of metals,antibiotic susceptibility and mer gene were ...Mercury-resistant strain D2 was isolated from mercury-contaminated soil and investigations on its 16S rDNA sequence,growth,minimal inhibitory concentrations(MICs) of metals,antibiotic susceptibility and mer gene were conducted.The strain D2 can grow in the medium containing 60 mg/L mercury ion.It presents more than 99% identity of 16S rRNA gene with Pseudomonas aeruginosa,and exhibits high MIC values for heavy metals and a large spectrum antibiotics resistance.The mer RT gene sequence was amplified from chromosome.Strain D2 is identified as Pseudomonas aeruginosa and the resistance to mercuric ion is related to chromosome.展开更多
A heterotrophic acidothermophilic bacterial strain,YNTC-1,was isolated from an acidic hot spring in Tengchong,Yunan,China.YNTC-1 grows at pH value of 1.5-8.0 and temperature of 40-70℃,with optimal pH and temperature ...A heterotrophic acidothermophilic bacterial strain,YNTC-1,was isolated from an acidic hot spring in Tengchong,Yunan,China.YNTC-1 grows at pH value of 1.5-8.0 and temperature of 40-70℃,with optimal pH and temperature at 3.0 and 55℃,respectively.The cells of the strain are in shape of short rod,with 1.0-1.2μm in length and 0.7-0.8μm in diameter,and with distinct spores at both poles of each cell.The predominant fatty acids in cellular membrane of the strain are C18:1ω7c.16s rRNA gene analysis reveals that this strain is closely related to Alicyclobacillus sendaiensis,with over 99%sequence similarity.Based on phenotypic and genotypic analyses,YNTC-1 is identified as a member of A.sendaiensis.Considering some important morphological and biochemical differences between strain YNTC-1 and A.sendaiensis ATCC 27009T,YNTC-1 may be proposed to be a novel subspecies of A.sendaiensis.However,this viewpoint has to be confirmed by further studies.Co-bioleaching of pyrite and chalcopyrite with strain YN22,Sulfobacillus thermosulfidooxidans,shows that strain YNTC-1 has no evident influence on bioleaching rates of these two sulphide minerals.展开更多
The toxicity of heavy metals (Hg2 + , Zn2 + ) and pesticides has been investigated by comparing the physiological properties in wild and tolerant strains of Synechococcus cedrorum 1191. The differential pattern of gro...The toxicity of heavy metals (Hg2 + , Zn2 + ) and pesticides has been investigated by comparing the physiological properties in wild and tolerant strains of Synechococcus cedrorum 1191. The differential pattern of growth, absorption spectra of pigments and nutrient uptake was observed in tolerant strain.展开更多
Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization ...Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization of fermentation conditions of HX-producing bacteria are essential for industrial CLFL production. In this study, one strain of HX-producing bacterium was isolated from six candidate bacterial strains and identified as Clostridium sartagoneforme. Then, the growth characteristics and HX production of C. sartagoneforme were investigated. Sodium acetate medium was identified as the optimal fermentation medium from four candidate media. C. sartagoneforme yielded 800.85 ± 12.87 mg/100mL HX in sodium acetate medium. Then, to further optimize the formula of the fermentation medium, the carbon and nitrogen sources and inorganic salt component of the fermentation medium were investigated using HX yields as an optimization index. Optimization was performed with a single-factor experiment and the Taguchi design method. The single-factor experiment showed that the highest HX outputs were obtained when the sodium acetate medium contained 2.5 g/L yeast extract, 1.8 g/L KCl, 20 g/L sodium acetate, 15 mL/L ethanol, and 1.5 g/L glucose. In the orthogonal experiment designed using the Taguchi design method, HX yields reached 2018.29 ± 46.37 mg/100mL in sodium acetate medium that contained 3.5 g/L yeast extract, 1.8 g/L KCl, 25 g/L sodium acetate, and 15 mL/L ethanol.展开更多
[Objective] The research aimed to screen out an efficient aniline-degrading strain and study its degradation characteristics. [Method] By domesticated enrichment culture, an efficient aniline-degrading strain named as...[Objective] The research aimed to screen out an efficient aniline-degrading strain and study its degradation characteristics. [Method] By domesticated enrichment culture, an efficient aniline-degrading strain named as DA-K was isolated from activated sludge sample collected from a chemical plant in Henan. DA-K could use aniline as the sole carbon and nitrogen sources. The strain was carried out physiological and biochemi- cal identification, and its biological degradation characteristics were studied. [ Result] DA-K strain was G - and red-shaped, and its colony color was off-white. It was initially determined as Acinetobacter sp. By measuring, the optimum growth temperature and pH for DA-K were respectively 30 ~C and 6.0. DA-K strain could grow well in inorganic salt medium with aniline of 2 500 mg/L. After shaking for 96 h under the conditions of pH 6.0, 30 ℃, 180 r/min and 1 000 mg/L of aniline, the degradation rate of the aniline by DA-K could reach nearly 80%. [ Conclusion] The DA-K strain had a higher aniline degradation efficiency and actual treatment capability of the aniline wastewater, which laid foundation for establishing gene engineerincl strain.展开更多
Two types of elastomeric vibration isolators used for equipment vibration isolation in aerospace vehicles are considered for the present study. These isolators are constructed using elastomers mounted in steel encasin...Two types of elastomeric vibration isolators used for equipment vibration isolation in aerospace vehicles are considered for the present study. These isolators are constructed using elastomers mounted in steel encasings. These isolators are initially deformed statically and dynamic loads are applied on the deformed configuration. To capture the static deformation, equivalent static load corresponding to its load rating and specified displacements are created. Static deformation is computed using Finite Element methods with four node axi-symmetric element which include the geometric non-linear effect for steel and with standard Yeoh hyper-elastic material model for elastomers(Muhammed and Zu, 2012) [1]. Yeoh material constants are derived from uni-axial tension test data of the elastomer specimen. These isolators are subjected to harmonic and random excitations in the pre-deformed state. For numerical analysis, elastomeric constants at dynamic conditions are obtained as complex function of frequency using Dynamic Mechanical Analyzer(DMA) for a range of frequencies. The standard material model of Yeoh is modified incorporating frequency dependant material characteristics and damping in the range of frequencies of interest. A multiplicative non-separable variables law is derived for Yeoh material model to include the effect of static pre-stress, based on the methodology given in literature(Nashif et al.,1985;Beda et al., 2014) [2,3]. The modifications of Yeoh model suitable for frequency domain analysis is the novelty in the present study. In the analysis, while dynamic loads are applied, the configuration is updated considering initial static loading. The frequency response of the isolators is computed using material properties evaluated at progressive dynamic strains until a match in natural frequency is observed. Appropriate damping corrections are then incorporated to match the test observed transmissibility. Then updated material properties are used to compute the random response which showed good agreement with results of experiments, validating the approach taken for the development of this model.展开更多
文摘An aerobic bacterium strain, F-3-4, capable of effectively degrading 2,6-di-tert-butylphenol(2,6-DTBP), was isolated and screened out from an acrylic fiber wastewater and the biofilm in the wastewater treatment facilities. This strain was identified as Alcaligenes sp. through morphological, physiological and biochemical examinations. After cultivation, the strain was enhanced by 26.3% in its degradation capacity for 2,6-DTBP. Results indicated that the strain was able to utilize 2,6-DTBP, lysine, lactamine, citrate, n-utenedioic acid and malic acid as the sole carbon and energy source, alkalinize acetamide, asparagine, L-histidine, acetate, citrate and propionate, but failed to utilize glucose, D-fructose, D-seminose, D-xylose, serine and phenylalanine as the sole carbon and energy source. The optimal growth conditions were determined to be: temperature 37℃, pH 7.0, inoculum size 0.1% and shaker rotary speed 250 r/min. Under the optimal conditions, the degradation kinetics of 2,6-DTBP with an initial concentration of 100 mg/L was studied. Results indicated that 62.4% of 2,6-DTBP was removed after 11 d. The degradation kinetics could be expressed by Eckenfelder equation with a half life of 9.38 d. In addition, the initial concentration of 2,6-DTBP played an important role on the degradation ability of the strain. The maximum initial concentration of 2,6-DTBP was determined to be 200 mg/L. Above this level, the strain was overloaded and exhibited significant inhibition.
基金supported by NSF(DMI-0328162 and ECCS-0824129)the National Natural Science Foundation of China (10820101048)Ministry of Education of China,and the National Basic Research Program of China(2007CB936803).
文摘Stretchable electronics represents a direction of recent development in next-generation semiconductor devices.Such systems have the potential to offer the performance of conventional wafer-based technologies,but they can be stretched like a rubber band,twisted like a rope, bent over a pencil,and folded like a piece of paper.Isolating the active devices from strains associated with such deformations is an important aspect of design.One strategy involves the shielding of the electronics from deformation of the substrate through insertion of a compliant adhesive layer. This paper establishes a simple,analytical model and validates the results by the finite element method.The results show that a relatively thick,compliant adhesive is effective to reduce the strain in the electronics,as is a relatively short film.
文摘To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different antibody titers were challenged with a Nigerian isolate of virulent IBDV. Mortality rates of the different groups were plotted against their respective mean PHA antibody titers. A group with zero antibody titer had a mortality rate of 75% while those with PHA antibody titers of 185.6, 243.2, 256 and 307.2 had mortality rates of 40%, zero, zero and zero respectively. Linear equation generated for a line of best fit of the graph of mortality rates of the chicks on their IBD antibody titers gave antibody titer (X) at which mortality (Y) would be zero as 300. A mortality of 75% and the high antibody level needed to protect chicks suggest that the isolate may be a hypervirulent strain.
文摘Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 (a specific local strain in China) of MDV. Methods\ Two oligonucleotide primers were synthesized according to the reported sequence of \%meq\% gene an ideal oncogenic candidate and our previously determined sequence of BamHI L fragment of Marek′s disease herpesvirus (MDV), respectively. Reverse transcriptase PCR(RT PCR) assay was performed by using these primers and the mRNA as a template which was isolated from visceral lymphoblastoid tumors obtained from chickens artificially infected with strain Beijing 1 of oncogenic MDV. Southern blot molecular hybridization was further carried out to detect the product of RT PCR with digoxigenin labeled nucleotide probe from BamHI I2 and L fragment in the gene library of MDV strain GA, respectively. Results\ Two probes could simultaneously hybridize this cDNA amplified by RT PCR with a length of about 730 bp. Conclusion\ It is suggested that \%meq\% transcription could extend from the right hand end of BamHI I2 to the adjacent BamHI L, and the BamHI L region was likely to be transcribed in MDV induced lymphoblastoid tumors.
基金Project(50621063) supported by the National Natural Science Foundation of ChinaProject(2004CB619204) supported by the National Basic Research Program of ChinaProject(2009sk3035) supported by the Science and Technology Program of Hunan Province,China
文摘Mercury-resistant strain D2 was isolated from mercury-contaminated soil and investigations on its 16S rDNA sequence,growth,minimal inhibitory concentrations(MICs) of metals,antibiotic susceptibility and mer gene were conducted.The strain D2 can grow in the medium containing 60 mg/L mercury ion.It presents more than 99% identity of 16S rRNA gene with Pseudomonas aeruginosa,and exhibits high MIC values for heavy metals and a large spectrum antibiotics resistance.The mer RT gene sequence was amplified from chromosome.Strain D2 is identified as Pseudomonas aeruginosa and the resistance to mercuric ion is related to chromosome.
基金Project(50621063)supported by the Chinese National Natural Science Foundation for Innovative Research GroupsProject(2004CB619201)supported by the Major State Basic Research Development Program of China
文摘A heterotrophic acidothermophilic bacterial strain,YNTC-1,was isolated from an acidic hot spring in Tengchong,Yunan,China.YNTC-1 grows at pH value of 1.5-8.0 and temperature of 40-70℃,with optimal pH and temperature at 3.0 and 55℃,respectively.The cells of the strain are in shape of short rod,with 1.0-1.2μm in length and 0.7-0.8μm in diameter,and with distinct spores at both poles of each cell.The predominant fatty acids in cellular membrane of the strain are C18:1ω7c.16s rRNA gene analysis reveals that this strain is closely related to Alicyclobacillus sendaiensis,with over 99%sequence similarity.Based on phenotypic and genotypic analyses,YNTC-1 is identified as a member of A.sendaiensis.Considering some important morphological and biochemical differences between strain YNTC-1 and A.sendaiensis ATCC 27009T,YNTC-1 may be proposed to be a novel subspecies of A.sendaiensis.However,this viewpoint has to be confirmed by further studies.Co-bioleaching of pyrite and chalcopyrite with strain YN22,Sulfobacillus thermosulfidooxidans,shows that strain YNTC-1 has no evident influence on bioleaching rates of these two sulphide minerals.
文摘The toxicity of heavy metals (Hg2 + , Zn2 + ) and pesticides has been investigated by comparing the physiological properties in wild and tolerant strains of Synechococcus cedrorum 1191. The differential pattern of growth, absorption spectra of pigments and nutrient uptake was observed in tolerant strain.
文摘Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization of fermentation conditions of HX-producing bacteria are essential for industrial CLFL production. In this study, one strain of HX-producing bacterium was isolated from six candidate bacterial strains and identified as Clostridium sartagoneforme. Then, the growth characteristics and HX production of C. sartagoneforme were investigated. Sodium acetate medium was identified as the optimal fermentation medium from four candidate media. C. sartagoneforme yielded 800.85 ± 12.87 mg/100mL HX in sodium acetate medium. Then, to further optimize the formula of the fermentation medium, the carbon and nitrogen sources and inorganic salt component of the fermentation medium were investigated using HX yields as an optimization index. Optimization was performed with a single-factor experiment and the Taguchi design method. The single-factor experiment showed that the highest HX outputs were obtained when the sodium acetate medium contained 2.5 g/L yeast extract, 1.8 g/L KCl, 20 g/L sodium acetate, 15 mL/L ethanol, and 1.5 g/L glucose. In the orthogonal experiment designed using the Taguchi design method, HX yields reached 2018.29 ± 46.37 mg/100mL in sodium acetate medium that contained 3.5 g/L yeast extract, 1.8 g/L KCl, 25 g/L sodium acetate, and 15 mL/L ethanol.
基金Supported by National Transgene Special Project, China(2008ZX2008005-001)Major Public Project in Henan Province,China (091100910500)
文摘[Objective] The research aimed to screen out an efficient aniline-degrading strain and study its degradation characteristics. [Method] By domesticated enrichment culture, an efficient aniline-degrading strain named as DA-K was isolated from activated sludge sample collected from a chemical plant in Henan. DA-K could use aniline as the sole carbon and nitrogen sources. The strain was carried out physiological and biochemi- cal identification, and its biological degradation characteristics were studied. [ Result] DA-K strain was G - and red-shaped, and its colony color was off-white. It was initially determined as Acinetobacter sp. By measuring, the optimum growth temperature and pH for DA-K were respectively 30 ~C and 6.0. DA-K strain could grow well in inorganic salt medium with aniline of 2 500 mg/L. After shaking for 96 h under the conditions of pH 6.0, 30 ℃, 180 r/min and 1 000 mg/L of aniline, the degradation rate of the aniline by DA-K could reach nearly 80%. [ Conclusion] The DA-K strain had a higher aniline degradation efficiency and actual treatment capability of the aniline wastewater, which laid foundation for establishing gene engineerincl strain.
文摘Two types of elastomeric vibration isolators used for equipment vibration isolation in aerospace vehicles are considered for the present study. These isolators are constructed using elastomers mounted in steel encasings. These isolators are initially deformed statically and dynamic loads are applied on the deformed configuration. To capture the static deformation, equivalent static load corresponding to its load rating and specified displacements are created. Static deformation is computed using Finite Element methods with four node axi-symmetric element which include the geometric non-linear effect for steel and with standard Yeoh hyper-elastic material model for elastomers(Muhammed and Zu, 2012) [1]. Yeoh material constants are derived from uni-axial tension test data of the elastomer specimen. These isolators are subjected to harmonic and random excitations in the pre-deformed state. For numerical analysis, elastomeric constants at dynamic conditions are obtained as complex function of frequency using Dynamic Mechanical Analyzer(DMA) for a range of frequencies. The standard material model of Yeoh is modified incorporating frequency dependant material characteristics and damping in the range of frequencies of interest. A multiplicative non-separable variables law is derived for Yeoh material model to include the effect of static pre-stress, based on the methodology given in literature(Nashif et al.,1985;Beda et al., 2014) [2,3]. The modifications of Yeoh model suitable for frequency domain analysis is the novelty in the present study. In the analysis, while dynamic loads are applied, the configuration is updated considering initial static loading. The frequency response of the isolators is computed using material properties evaluated at progressive dynamic strains until a match in natural frequency is observed. Appropriate damping corrections are then incorporated to match the test observed transmissibility. Then updated material properties are used to compute the random response which showed good agreement with results of experiments, validating the approach taken for the development of this model.