bluuebunny/crossref_metadata_2025 huggingface dataset:
An Host-Guest Electrochemical Sensor for DNA Ligase Detection
Authors: Xiong Wei , Ding Yan Hua , Zhang Xiu Xiu , Fan Hao
Published: October 2014

We herein constructed a electrochemial sensor for T4 DNA ligase detction. In the sensor, the hairpin dsDNA terminal-labeled with 4-((4-(dimethylamino)phenyl)azo)benzoic acid (dabcyl) and thiol group was immobilized on Au electrode surface as the probe by Au-S bond, and the CdS nanoparticles surface-modified with β-cyclodextrins (ZnS-CD) were employed as electrochemical signal provider and host-guest recognition element. After T4 DNA ligase repairing single-strand breaks in duplex DNA, the dsDNA probe underwent a significant conformational change, which forced dabcyl away from the electrode. As a result, formerly shielded dabcyl became accessible to host-guest recognition between β-cyclodextrin and dabcyl, thus the target repairing event could be sensitively transduced to electrochemical signal provided by ZnS-CD.
Determination of Rhodium in Waste Thiourea Rhodium Samples Using Teflon Pressure Vessel-Assisted Sample Digestion and ICP-OES
Authors: Xie Zhi Ping , Wei Xiao Juan
Published: October 2014

A novel method for the determination of rhodium in waste thiourea rhodium samples was established by inductively coupled plasma optical emission spectrometry after samples digested by Teflon pressure digestion vessel with aqua regia. Such experiment conditions were investigated as the influence of sample dissolution methods, digestion time, digestion temperature and interfering ions on the determination. Under the optimized conditions, the limit of detection (LODs) of Rh for tested solution was 9 ng mL-1. The relative standard deviations (RSDs) for Rh was 1.98 % (CRh = 1 mg L-1, n = 7). The linear range of calibration graph for Rh was 0 ~ 150.00 mg L-1. The proposed method was applied to determine the practical samples with good recoveries and satisfactory results.
Study on Identification of 100% Cotton Fabric by Raman Spectroscopy and Random Forest
Authors: Luo Jun , Xie Jian Fei , Fan Wei
Published: October 2014

The analytical method was established for identification of 100% cotton fabric by Raman spectroscopy. 100 samples were analyzed directly by Raman spectrometer with a 1064nm laser source. 1120-1180 cm-1,1320-1400cm-1 and 1560-1600cm-1 were selected as important spectral regions by Random forest method. A Random forest model was established with 65 trees and 80 training samples. The result showed that different kind of textile can be identified by Raman spectroscopy coupled with random forest method.
Influence of Distance from Blast Center on Time-Frequency Characteristics of Blast Vibration Signals
Authors: Zhao Ming Sheng , Wang Xu Guang , Chi En An , Kang Qiang
Published: October 2014

The distance from the blast center will directly change the blasting seismic wave wave’s energy property and eventually influence the structure’s response to the wave. To study its influence on the time-frequency (t-f) characteristics of blasting vibration signals, the single-hole blasting vibration test was conducted in Jinduicheng Open Pit Mine. Based on the measured data, wavelet analysis was used to decompose the measured signals, and signal segments at different frequency bands were got. RSPWVD quadratic form time-frequency analysis method was applied to analyze the segments’ t-f characteristics, and the domain frequencies of the blasting seismic waves under different distances from the blast center and the energy distribution and duration of the frequency bands were collected. The results show that the distance from the blasting center has a big impact on the domain frequency of the blasting seismic wave. With the increasing of the distance, the domain frequency reduces, its duration extends, the percentage of energy at the low frequency in the total energy increases and the duration of the frequency band extends. The research results provide the analysis base for understanding the influence of the distance from the blast center on signals’ t-f characteristic and studying vibration resistance and vibration reduction.
Electrocatalytic Performance of PbNP-MWCNTs Composite Electrode toward Glucose
Authors: Hong Xiao Ping , Ma Jing Ying
Published: October 2014

This work reported a new approach for the preparation of a promising lead nitroprusside (PbNP) and multi-walled carbon nanotubes (MWCNTs) composite electrode, which exploited the synergistic advantages of PbNP and MWCNTs. And the electrocatalytic performance of the new composite electrode toward glucose was also studied. Comparing with MWCNTs modified electrode and glassy carbon electrode, the new composite electrode exhibited advantages of low applied potential, high current response, good stability and reliability. The PbNP-MWCNTs composite electrode had superior performance, which was expected a good candidate for reliable glucose detection.
Finite Element Simulation and Experimental Analysis of O-P Hardness
Authors: Huang Yong , Ma De Jun , Chen W. , Wang Jia Liang , Sun Liang
Published: October 2014

Based on the finite element analysis method to simulate the O-P hardness. Taking S45C steel as an example, comparative analysis of O-P hardness of finite element simulation and O-P hardness of instrument indentation hardness experiment, results show that difference of S45C steel’s O-P hardness between the finite element simulation and real experiment is-2.62% Accordingly seen, O-P hardness can be obtained by finite element numerical simulation method, it’s a possible way to study relations between O-P hardness and Vickers hardness based on finite element numerical simulation techniques.
Effects of Different Kinds of Supporting Electrolyte on the Electrochemical Test of T501
Authors: Liu Chen Yao , Wang Na Na , Huang Yun Guang , Tan Xue Yuan , Zhu Li Ping , Yu Wei Wei , Zhu Zhi Ping
Published: October 2014

The functions of transformer oil in the transformer were insulation and cooling, its position was very important. Oil usually keeps its good oxidation resistance by adding antioxidants, the most common used antioxidants in the transformer oil was T501, the oxidation rate of oil could be delayed significantly by adding it, thereby the life of oil would be prolonged. But the electrochemical performance of oil would be affected by the excessive addition of antioxidants, so it was important to determine the content antioxidant precisely. This paper mainly studied under the three electrode system, the determined electrode material and electrode size, studied the influence of support electrolyte species on the determination of T501 by electrochemical methods, choose the most suitable electrolyte solution type. It was further demonstrated that the working electrode was a 4 mm-diameter graphite electrode, Pt coil was used as the counter electrode, the reference electrode was a calomel electrode, the optimum electrolyte was KOH, optimum organic solvent was 98% ethanol solution.
An Efficient Solvent-Free Synthesis of Bis(2-Tetrahydrobenzofuranyl)Alkanes Catalyzed by H2SO4•SiO2
Authors: Zhang Fan , Xiao Lu Lu , Jin Lei , Wang Wen Bin , Huang Nian Yu
Published: October 2014

A series of bis (2-tetrahydrobenzofuranyl) alkanes in good yield under solvent-free conditions from differently aromatic substituted aldehydes and 3-methyl-6,7-dihydrobenzofuran-4(5H)-one in the presence of H2SO4•SiO2as catalyst at 90oC. Their structures were characterized by NMR, IR and ESI-MS. The proposed mechanism for the H2SO4•SiO2-catalyzed condensation reaction have been discussed in the work. This versatile approach has the advantages of broad functional group compatibility, short reaction times, simple operation and environmentally benign nature.
Mesoscopic Dynamic Simulations of Poly (Methyl Methacrylate) and Poly (Ethylene Oxide) Blends
Authors: Zhang Min , Zhang Guo Fang , Jia Yu Xi
Published: October 2014

In this work, we use Mesoscopic Dynamic (MesoDyn) density function simulation to study the compatibility of polymer blends. The mesoscale model for Poly (methyl methacrylate) (PMMA) and Poly (ethylene oxide) (PEO) were set up. The free energy, enthalpy, entropy, order parameters and density profiles were got by the simulation. The results showed that the free energy density keeps constant negative value and the order parameters is much less than 0.1. And phase separation behavior was not observed during the whole simulation time. Using density profiles, the kinetics of phase separation was examined and the phase separation behavior. These indicates that PMMA and PEO is miscible.
Molecular Dynamic and Mesoscopic Dynamic Simulations for Polymer Blends
Authors: Zhang Min , Zhang Guo Fang , Jia Yu Xi
Published: October 2014

The compatibilities of polymer blends, Polypropylene (PP) and Polyamide12(PA12) with the quantity ratio 10/90, was simulated by Molecular Dynamics (MD) and Mesoscopic Dynamic simulation (MesoDyn) simulations. Cohesive energy density (CED) and solubility parameters (δ) of pure substances and PP/PA12 blends were got by MD simulations. Flory-Huggins parameter was calculated based on CED values. The mesoscale simulation was related to the molecular simulation through Flory-Huggins parameter. Free energy density and the density profiles were got through MesoDyn simulation. Results showed that solubility parameter difference (Δδ) of PP/PA12 is 4.092 and free energy density value is 0.17 in the equivalent system. And phase separation behavior was observed in the density profiles. All these indicates that PP and PA12 is not miscible which is the same as the experiment results.
Parameter Study of Numerical Analysis on Low-Velocity Impact of GLARE 5 Fibre-Metal Laminates
Authors: Wan Yun , Huang Xin Lei , Zhou Li Min
Published: October 2014

The impact performance play an important role to marine material. A numerical methodology including user material subroutine VUMAT, Johnson–Cook flow stress model and surface-based cohesive behaviour is employed to simulate the damage of the impact of GLARE 5 fibre-metal laminates (FML). Not only histories of absorbed energy, deflection, contact force are presented in our simulation, but the interface delamination is also investigated. After parameter study, suitable fracture energy in surface-based cohesive behaviour was found.
Combined Determination of Phosphorus and Arsenic in Molybdenum Concentrate by Molybdenum Blue Spectrophotometric Method
Authors: Zhou Cheng Ying , Qu Wei , Cai Liu Lu
Published: October 2014

This paper determined the total absorbance of phosphorus molybdenum blue and arsenic molybdenum blue by using the additive property of their absorbance values. By eliminating the interference of arsenic by reduction masking with composite reducing agent Na2SO3-Na2S2O3-KBr, the absorbance of phosphorus could be obtained. Thus, the content of phosphorus and arsenic could be calculated, respectively. The results show that the work curves of this method for phosphorus and arsenic are consistent with Beer’s law when the content of phosphorus and arsenic is 0-0.60ug/mL and 0-2.00ug/mL, respectively. The standard addition recovery rate of phosphorus and arsenic is 98.80%-101.04% and 99.00%-101.50%, respectively. The relative standard deviation of phosphorus and arsenic is less than 4.0% with good accuracy and precision. This method is simple and fast to determine phosphorus and arsenic in molybdenum concentrate, and the results are accurate and reliable.
Construction of Chiral Hydroxyl of the Intermediate of Strictifolione by Using Evans Auxiliary
Authors: Wang Gao Peng , Wang Li Ping , Qin Shuang Lin , Huang Fei Fei , Huang Shuang Ping , Wang Xiao Ji
Published: October 2014

The key intermediate of strictifolione was synthesized via an Evans aldol reaction to construct its chiral hydroxyl.
Study on Synthesis of Tert-Butyl(4R)-4-(Methoxymethylcarbamoyl)-2,2-Dimethylthiazolidine-3- Carboxylate
Authors: Qin Shuang Lin , Tang Lin Jun , Wang Gao Peng , Wang Li Ping , Huang Fei Fei , Huang Shuang Ping , Wang Xiao Ji
Published: October 2014

Tert-butyl (4R)-4-(methoxymethylcarbamoyl)-2,2-dimethylthiazolidine-3-carboxylate, an key intermediate of the natural product Biotin which is a water-soluble vitamin, involved in an essential part of the metabolic cycle causing catalytic fixation of carbon dioxide in the biosynthesis of fatty acids, sugars, and α-amino acids, was synthesized from L-cystine in overall yield 54% through three steps. The study including acetonization, Boc protection, N-methoxy-N-methyl amidation.
Synthesis of (5R,7R)-Methyl3,5-Dihydroxy-7-((4-Methoxybenzyl)Oxy)Octanoate
Authors: Tang Lin Jun , Huang Fei Fei , Liu Dong Wang , Li Yu Ping , Huang Shuang Ping , Wang Xiao Ji
Published: October 2014

(5R, 7R)-methyl3, 5-dihydroxy-7-((4-methoxybenzyl) oxy) octanoate (2), as a key intermediate for the total synthesis of tarchonanthuslactone, was reported, which started from (R)-3-((4-methoxybenzyl) oxy) butanal (3) through few steps.
Synthetic Study towards Aculeatin A and B
Authors: Zhang Jian Ting , Zhu Cheng Lin , Chen Shi Peng , Wang Rui , Huang Shuang Ping , Wang Xiao Ji
Published: October 2014

A practical and diastereoselective synthetic study towards the cytotoxic and antimalarial compounds aculeatin A and B is described, which started from commercially available 1-tetradecanol and proceeded through a key Evans aldol reaction.
Liquid Phase Hydrogenation of Maleic Anhydride over Ni Catalysts: Effect of Support on the Catalytic Performance
Authors: Xu You Min , Bi Ya Dong , Yin Xiao Hong
Published: October 2014

Ni catalysts supported on CeO2 and HZSM-5 supports were prepared and tested as catalysts in the liquid hydrogenation of maleic anhydride. Particularly Ni/HZSM-5 was active and selective in the hydrogenation of maleic anhydride to ڃ-butyrolactone. The characterization results of X-ray diffraction (XRD), N2 adsorption and CO temperature programmed reduction (CO-TPR) evidenced that the higher C=O hydrogenation ability of Ni/HZSM-5 catalyst was related to strong interaction between Ni particles and HZSM-5, and the high dispersion of fine Ni particles on the surface of support. Further, the acidic HZSM-5 support benefits the dehydration performance during the C=O bond hydrogenation process, which favored the production of ڃ-butyrolactone. The dual-functional Ni/HZSM-5 catalyst possesses both hydrogenation and dehydration activity.
Synthetic Study towards Salvianolic Acid A: Synthesis of the Intermediate of (3, 4-Bis((Tert-Butyldimethylsilyl)Oxy)-Benzylidene)Triphenylphosphorane
Authors: Wang Li Ping , Liu Dong Wang , Qin Shuang Lin , Wang Gao Peng , Wang Xiao Ji , Huang Shuang Ping
Published: October 2014

Synthesis of (3, 4-bis ((tert-butyldimethylsilyl) oxy)-benzylidene) triphenyl- phosphorane, an important intermediate of salvianolic acid A (1), was reported, which synthetic route including protection, bromation and Wittig salt formation.
Improvement on Determination of the Adsorption Value of Activated Carbon on Methylene Blue
Authors: Huang Zhao Long , Feng Shao Ping , Jiang Yan , Xiao Rui Min , Sun Li Da , Lu Shun Li
Published: October 2014

Characteristics of absorption of activated carbon on methylene blue were studied. It was demonstrated that adsorption of activated carbon on methylene blue was very stable on monomolecular adsorption and when multimolecular adsorption existed adsorption became to be weak. An improved method was suggested that many samples were tested adsorption of activated carbon on methylene blue in parallel experiment and certain sample was selected to use in next experiment, its color should approximate to the color of 0.4% CuSO4 but darker slightly and activated carbon loaded methylene blue was added some fresh phosphate buffer solution to desorb methylene blue on the activated carbon, testing absorption value total concentration of methylene blue in the solutionin (merging the first and second experiment) by spectrophotometer, calculating adsorption value on difference method which original volume of methylene blue added subtracts rest of methylene blue in the solution after adsorption. The new method was simple, rapid and easy. word times would shorten obviously.
Synthesis and Crystal Structure of an Oxovanadium(IV) Complex Containing L-Phenylalanine Schiff Base and 1,10-Phenanthroline
Authors: Dong Jian Fang , Jing Bu Qin , Li Lian Zhi
Published: October 2014

A new oxovanadium (IV) complex, [VO(o-van-phe)(phen)] (1) (o-van-phe = Schiff base derived from o-vanillin and L-phenylalanine, phen =1,10-phenanthroline), has been synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The results show that complex 1 belongs to triclinic crystal system, with P-1 space group, a=10.646(2) Å, b=11.089(3) Å, c=14.143(4) Å, α=67.374(4)°, β=79.685(4)°, γ=89.711(4)°, Z=2, V=1512.5(7) Å3, Dc =1.195 mg·m–3, μ=0.366 mm–1, F(000)=562. In the molecular structure, the V(IV) ion is six coordinated to form a distorted octahedral geometry. In the crystal, a dimer is formed by intermolecular hydrogen bonding and π–π stacking interactions.
Study on Synthesis of (R)-Tert-Butyl Benzyl(1-((Tert-Butyldimethylsilyl)Oxy)But-3-Yn-2-Yl)Carbamate
Authors: Tang Lin Jun , Liu Dong Wang , Qin Shuang Lin , Wang Li Ping , Li Yu Ping , Huang Shuang Ping , Wang Xiao Ji
Published: October 2014

(R)-tert-butyl (1-hydroxybut-3-yn-2-yl) carbamate, an intermediate of the natural product jaspine B, which was isolated from various sponges and endowed with cytotoxic activity against several human carcinoma cell lines, was synthesized fromL-Serine in overall yield 30% through seven steps, including esterification, Bn protection, Boc protection, TBS protection, reduction, Corey-Fuchs reaction.
Synthesis and Radical Polymerizations of N-Substituted Maleimide Bearing Two Olefinic Groups
Authors: Gao Hua Jing , Jin Zhao Hui
Published: October 2014

A kind ofN-substituted maleimide - having two olefinic bonds with different reactivities, (S)-N-Maleoyl-L-leucine allyl ester ((S)-ALMI), was synthesized from maleic anhydride, L-leucine and allyl alcohol. Radical polymerizations were carried out to obtain optically active polymers using 2,2′-azobisisobutyronitrile. Structures of the monomer and polymers obtained were investigated by NMR measurements. In radical polymerizations, the solvents strongly affect the radical polymerization behaviors of (S)-ALMI.
Comparison of Aromatic Substances in Buckwheat Vinegar that Adding the Moldy Bran, Drug Koji and A.schutzenbachii during Fermentation
Authors: Zhang Xin Min , Ma Ting Jun , Yang Xiu Shi , Qin Pei You , Liu San Cai , Ren Gui Xing
Published: October 2014

In order to study the impact of moldy bran, drug koji andA.schutzenbachiifermentation vinegar on the aromatic substances in buckwheat vinegar, vinegars that adding moldy bran, drug koji andA.schutzenbachiiwere used to analyze the content of aromatic ingredients with GC-MS method. The results indicated that buckwheat vinegar by drug koji fermentation includes 29 kinds of aromatic substances, moldy bran fermentation buckwheat vinegar has 23 kinds of aromatic substances,A.schutzenbachiifermentation vinegar contains 20 kinds of aromatic substances.
Effects of Cold Preservation on Quality and Sarafloxacin and Difloxacin Residues in Beef
Authors: Wang Qian , Jin Yue , Yang Yi Qing , Deng Jie , Ma Li Zhen , Yan Shi Jie
Published: October 2014

During cold preservation, the pH and moisture of beef decreased slowly. Changes in ash and protein content had no obvious rules, but the data analysis results showed that the effect of drugs on these indexes was significant. Ca, Fe content decreased, Zn content increased, TBARS values were significantly higher than those in the blank , and violent fluctuation. SAR and DIF had obvious bacteriostasis effect. Cold preservation had no palpable effect on fluoroquinolones residues.
Effects of Different Freezing Rates on the Quality Changes in Cooked Crayfish (Procambarus clarkia) Meat during Frozen Storage (-20°C)
Authors: Zhao Li , Chen Jun , Zhao Xi Rong , Wang Zong Yao
Published: October 2014

Changes in physical, chemical, microbiological and sensory qualities of cooked crayfish (Procambarus clarkia) meat, treated at different freezing rate (-30°C,CPF; -60°C,ULTF; -196°C,LNM), were investigated during storage at -20°C for up to 6 months. pH value increased in all treatments with the sharp reduction after 3 months. Increase in weight loss of LNM was slower than that of CPF and ULTF cooked crayfish. During frozen storage, thiobarbituric acid value (TBA value) fluctuated in all treatments, but lipid oxidation did not affect the quality of crayfish meat because of its lower fat contents. Total volatile basic nitrogen (TVB-N) increased with storage time, with the reduction of TVC and sensory score. Freezing rates could not cause significant changes in chemical qualities (pH value, total volatile basic nitrogen, thiobarbituric acid value), sensory quality and microbiological quality for all three treatments during storage. In spite of decrease of quality of cooked crayfish meat in all treatments, good edibility was kept throughout the storage.
Effects of Exogenous Ethylene on AC and Rin Tomato Fruit
Authors: Li Ling , Liu Hai Xue , Peng Yong Bo , Li Shi , Liu Tie Ling
Published: October 2014

The flesh firmness of AC andrinmutant tomato fruits picked freshly were the largest. Respiration rate and ethylene production were very low at this time. With ethylene production increase, fruit firmness began to decline. 100μL/L ethephon significantly increased AC tomato fruit ethylene release, respiration rate, ACS activity and ACO activity, and decreased flesh firmness. However, there were no significant differences inrinmutant between control and ethephon treatment. It was shown RIN transcription factor regulated ethylene biosynthesis by ACC synthase and ACC oxidase.
Factors that Affected Cooked Chestnut Kernel Browning
Authors: Shi Xiao Jun , Wang Fang , Pang Mei Xia , Huang Man Qing , Qi Jing Hua
Published: October 2014

Non-enzymatic browning often occurs in the processing of chestnut kernel.Chemical components of chestnut kernel that related to the browning have been studied in this paper in order to control the browning. Results were showed as followed: after the non-enzymatic browning in processing,the protein content of the cooked chestnut kernel decreased by 30.34%, reduced sugar content decreases by 38.44% and ascorbic acid content decreases by 85.81%. Therefore, Maillard reaction and ascorbic acid oxidation were the main reactions resulting in the browning of cooked chestnut kernel. In addition, the influence of pH is significant while sucrose and sodium chlorine had no effects on the non-enzymatic browning. Solution with pH of 3,4,or 5 displayed rather good effects on inhibiting the browning of cooked chestnut kernel.
Influences of 1-MCP on AC Tomato Fruit Softening
Authors: Li Ling , Wang Rui , Cao Yu Hui , Liu Zheng , Liu Tie Ling
Published: October 2014

The influences of 1-MCP on AC tomato fruit softening were investigated. Ethylene production, flesh firmness, protopectin content, soluble pectin content and polygalacturonase (PG) activity were used to evaluate the quality of tomato fruit. It was shown that 1.0 and 1.5 μL/L 1-MCP treatment significantly decreased the levels of ethylene production, and inhibited flesh firmness and protopectin content decline and polygalacturonase activity increase. At last, it was concluded 1.0 μL/L 1-MCP treatment on AC tomato fruit was the best determining economy.
A New Technological Study on Synthesis of Bis(2-chloroethoxy)Methane
Authors: Bai Yan , Tang Xuan , Zhou Kui , Zhang Cun She
Published: October 2014

bis(2-chloroethoxy)methane was synthesized by the reaction of ethylene chlorohydrin and Oligopolyformaldehyde under sulfuric acid catalysis. optimum reaction conditions obtained were as follows: the molar ratio of Oligopolyformaldehyde and ethylene chlorohydrin of 1.2:2, catalyst dosage was 5‰mass fraction of ethylene chlorohydrin, toluene were chose as water-carrying agent, All reactant were refluxed on temperature of 110°C until no water generated. Under the optimum conditions the yield of bis(2-chloroethoxy)methane was 97.7%. The structure of bis(2-chloroethoxy)methane were conformed by ATR IR. The purity of bis(2-chloroethoxy)methane were 99% by gas chromatographic detection.
Optimization of Extracting Condition of Active Components in Perilla by Ultrasonic
Authors: Huang Dan , Liu You Qing , Liang Yuan , Mao Xiang
Published: October 2014

Using ultrasonic-extraction technology, the condition of extracting the active compounds-flavonoids and rosmarinic acid ofPerillawas studied. The effects of four main factors include ultrasonic power, temperature, time and solid-liquid ratio on the extraction-rate of the flavonoids and the rosmarinic acid ofPerillawere reviewed by single factor experiments,and the flavonoids and the rosmarinic acid was determined by NaNO2-Al (NO3)3-NaOH method and FeSO4method. On the base of single factor experiments, the extraction technique was optimized in the orthogonal test. The result showed that temperature was the most important factor in the influencing factors on the extraction-rate. The subsequence of importance was temperature > time > solid-liquid ratio > ultrasonic. The optimal extraction conditions were: extraction solvent 3%borax, solid-liquid ratio 1:50(w/v), ultrasonic power 300W, time 90min , temperature 75°C. Under the optimum technological conditions, 34.64mg/g of flavonoids and rosmarinic acid fromPerillacould be obtained.
Optimization of Subcritical 1,1,1,2-Tetrafluoroethane( R134a ) Removal of Cholesterol from Spray-Dried Sthenoteuthis oualaniensis Egg Powder Using Response Surface Methodology
Authors: Sui Xiao , Feng Xiao Mei , Yue Rong Yan , Han Yu Qian , Xue Chang Hu
Published: October 2014

Subcritical 1, 1, 1, 2-tetrafluoroethane (R134a) extraction was applied to remove cholesterol from spray-dried Sthenoteuthis oualaniensis egg powder. Response surface methodology (RSM) was applied to optimize the parameters of subcritical R134a extraction (pressure, temperature, and extraction time) on removal rate of cholesterol. Response surface analysis showed that the data came to a precise fitting to a second-order polynomial model. The quadratic terms of pressure and temperature had high significant negative effects (p＜0.001) on removal rate. The optimum parameters of the variables were 8.6 MPa, 55.4 °C, 50 min. Under these conditions, removal rate of cholesterol was predicted to be 101% and experiments gave out the removal rate of 99.16%, which concurred with the model prediction. Furthermore, the removal efficiency of cholesterol by R134a was higher than those achieved by using supercritical carbon dioxide(SC-CO2)and β-cyclodextrin extraction methods.
Research on Detecting Aluminum in Jellyfish by Flame Atomic Absorption Method
Authors: Yang Xian Qing , Wu Ze Ye , Cen Jian Wei , Wei Ya , Hao Shu Xian , Zhou Wan Jun
Published: October 2014

The flame atomic absorption method was applied to determine aluminum in jellyfish. The optimum detecting conditions were determined through many experiments. It established a nitric oxide-acetylene flame atomic absorption method to detect aluminum content in jellyfish that a good linear relationship is obtained in concentration range and correlation coefficient r2=0.9996. There are no significant differences in results after jellyfish samples were digested by three pretreatment methods. The detection limit of this method is 3.5 mg/L, the relative standard deviations are less than 5%, and the recovery is in the range of 88.50~104.20%. The test shows that: both the precision and accuracy accord with the demands, so this instrument analytical method could apply to research on quantitative detection of aluminum in jellyfish.
Research on the Extraction and Purification of Dihydromyricetin from Ampelopsis grossedentata
Authors: Guo Jie Zhi , Tang Hao Guo , Yao Hong Juan , Zhang Yan Mei
Published: October 2014

Extracting dihydromyricetin from Ampelopsis grossedentata by water extraction method. The orthogonal test and single factor experiment were used to optimize the best extraction condition. The ratio of liquid and material is 20:1, extraction time is 90min, extraction temperature is 90°C,holding time is 1d. The results of comparison between two purification methods show: Purify with acetone and recrystallization with water is better. The purity of dihydromyricetin is high to 98%, recovery rate was 59.2%.
Determining the Impact of Celery Powder and Starter Culture on Quality of Indirectly Cured, Emulsified Cooked Sausages
Authors: Liu Cai Hong , Li Pei Ran , Yue Lan Xin , Guo Yao Hua , Fan Xiao Pan , Li Peng , Ma Li Zhen , Kong Bao Hua
Published: October 2014

The objective of this study was to determine the effect fresh celery powder and starter culture (FCP+SC), blanching celery powder and starter culture (BCP+SC) had on the quality characteristics of indirectly cured sausages, Two treatments (TRT) (TRT 1: FCP+SC, 0.3%FCP+0.033%WBL-45; TRT 2: BCP+SC, 0.3%BCP+0.033%WBL-45 ), Negative Control (NC) (no-nitrite-added control), Positive Control (PC) (0.1%sodium nitrite-added control) were investigated. Residual nitrite levels throughout storage is always higher in PC than FCP+SC and BCP+SC(P< 0.05), but in TBARS, PC is better than FCP+SC and BCP+SC(P< 0.05). Few differences existed between TRTs and PC for a* and gel strength. The processing methods investigated to manufacture “naturally cured” in this study were applied for products instead of sodium nitrite.
The Classification of Oak Barrel and the Effect on Wine
Authors: Li Chun Feng , Liu Ming Li , Liu Yan Long , Tang Zhao Fa
Published: October 2014

the objective of this study reviewed for the classification of the oak barrels, the influence of oak barrels on wine quality and the use of the oak barrels. Generalized the characteristics of the different plant sources oak barrels, summarized the important roles of the age of the oak barrels for stability, aroma, taste characteristics of wine; introduced several processing methods for oak barrels. This paper offered to reference to choose oak barrels for according to the qualities of the wine.
Analysis Hierarchy Process in Real Problem Resolution in a Food Company
Authors: Rosa Carla Regina Mazia , Arns Steiner Maria Teresinha , Colmenero João Carlos
Published: October 2014

One of the most important aspects to be considered by Distribution Centers (DCs) is the improvement of the process in relation to the attributes of the service that is provided. The purpose of this article is to analyze various alternatives for the definition of a DC with the use of a method of multi-criteria support in decision making, more specifically, the Analytic Hierarchy Process (AHP) for the allocation and weighting of importance levels for structuring DCs. To further illustrate the process, a field study was conducted in a multinational company in the food sector. This enabled the identification of the best of three possible structures that were evaluated based on the criteria and sub-criteria targeted in the decision context. The results show that the cost and quality factors are primarily responsible for choosing the most appropriate alternative.
Ultrasound-Assisted Oxidative Desulfurization of Diesel Fuel in H2O2/Heteropoly Acid/Solvent System
Authors: Yu Guo Xian , Zhong Qian , Jin Mei , Lu Ping
Published: October 2014

Ultrasound-assisted oxidative desulfurization (UAODS) of diesel fuel in H2O2/Heteropoly acid/Solvent systems, was investigated. Effects of solvent, catalyst, ultrasound and reaction temperature on the oxidation desulfurization of diesel fuel were investigated. When MPA/oil was 2%wt, methanol/diesel fuel was 20%wt, ultrasound power was 400 W and ultrasound time was 10 min, the sulfur content of diesel fuel was decreased from 211 ppm to 19 ppm. The use of ultrasonic irradiation in H2O2/Heteropoly acid/Solvent system significantly improved the efficiency of the oxidation reaction, and solvent was helpful to make the oxidative reaction happen in the same one phase.
A nth-Order Shear Deformation Theory for the Free Vibration Analysis of the Isotropic Plates on Elastic Foundations
Authors: Wang Feng , Xiang Song
Published: October 2014

A nth-order shear deformation theory for free vibration of the isotropic plates resting on a two-parameter Pasternak foundations is developed. The present theory does not require shear correction factor, and satisfies the zero transverse shear stress boundary conditions on the top and bottom surface of the plate. Governing equations are derived from the principle of virtual displacements. Meshless global collocation method based on the thin plate spline radial basis function is used to solve the governing differential equations. The accuracy of the present theory is demonstrated by comparing the present results with available published results.
Effect of Graphite Content on Corrosion Resistance of Zirconia Graphite Materials
Authors: Qian Fan , Yang Wen Gang , Yu Jian Bin , Ma Tian Fei , Liu Guo Qi
Published: October 2014

The effect of graphite content on formation of decarbonization layer and corrosion resistance of zirconia graphite materials were studied by the corrosion test in induction furnace, and the effect of decarbonization layer on corrosion of zirconia graphite materials was also analysed by the kinetic models for the corrosion of SEN in mold, the result show that Thickness of decarbonization layer of slag line is decreasing with the increase of graphite content. Corrosion of zirconia graphite materials in steel liquid / slag interface is characterized by the features of consecutive reaction:original layer→decarbonization layer→corrosion layer, and k1, and k2 are their reaction rate constant respectively.when we adjust graphite content, k1 and k2 will be change in opposite directions, so graphite content with well corrosion resistance depend on the condition of continuous casting
Finite Element Analysis of Influence of Nanoparticle on Hybrid Composites Reinforced by Fiber and Nanoparticle
Authors: Wang Xiao Qiang , Zhao Wei Tao , Fang Bo , Zhang Ye Wei
Published: October 2014

In order to improve the strength and toughness of materials, nanoparticle is always embedded into epoxy resin and fiber composite materials. The influence of the number, distribution and mechanical property of nanoparticle arranged around the fiber on fiber reinforced composites is evaluated in this paper. A finite element analysis under a tensile load is performed by using commercial finite element software named as ABAQUS. Both the stress contour and progressive damage failure mode of the representative volume element (RVE) model of fiber reinforced composites are obtained. A series of computational experimental results indicate that both the space geometry property and mechanical property of nanoparticle have a significant effect on the stiffness and strength properties of these composite materials.
In Situ Fabrication of TiC/Fe Composites by SHS Technology
Authors: Lv Ying , Li Jun Gang , Wu Ming Zhong , Zhang Xiao Peng , Wu Hai Tao
Published: October 2014

TiC/Fe composites were successfully fabricated in situ by self-propagating high temperature synthesis (SHS) technology. The effect of Fe content on the microstructure of the synthetic products was discussed. Results showed that the SHS products of Ti-C-30wt%Fe system were mainly composed of TiC and Fe as well as a few Fe2Ti.Spherical TiC particles with 2-3μm distributed on the Fe matrix uniformly. With the increase of Fe content, the combustion temperature reduced, resulting in the decrease of growth rate of TiC particles.
Phase Stability and Thermal Conductivity of La2O3, Y2O3 Stabilized ZrO2 Ceramic for Thermal Barrier Coating Application
Authors: Liu Huai Fei , Xiong Xiang , Wang Ya Lei
Published: October 2014

Rare earth oxides co-doped zirconia has been developed for application in thermal barrier coating (TBC) systems to promote the performance and durability. In this paper, the phase stability and thermal physical properties of 1mol.%La2O3, 4.5mol.%Y2O3stabilized ZrO2(LaYSZ) were investigated. After 100 h heat treated at 1400°C, the content of monoclinic phase in LaYSZ was 2.32 mol%, which is lower than that in YSZ (46.9 mol%). Result indicates that the LaYSZ has better phase stability and lower thermal conductivity than YSZ. The LaYSZ system can be explored as the candidate material as ceramic layer in TBC.
Processing and Mechanical Properties of Natural Rubber/Chitosan/Poly(3-hydroxybutyrate) Blends
Authors: Lu Guang , Huang Hong Hai , Yu He Ping , Wang Yong Zhou
Published: October 2014

In an attempt to improve the properties of natural rubber-based medical products, natural rubber (NR) was blended with chitosan (CS) and poly(3-hydroxybutyrate) (PHB) in an laboratory type internal mixer, with the total amount of CS and PHB is of 1, 3, 5, 10, 15 and 20 parts per hundred rubber (phr) , and CS and PHB is of a ratio of 1:1. The testing for processing properties of NR/CS/PHB compounds showed that the Mooney viscosity of NR/CS/PHB compounds increased with the addition of 1.0 phr CS/PHB and then decreased with increase in CS/PHB content, but the Mooney viscosity of each NR/CS/PHB compound was higher than that of NR compound; the minimum torque (ML) increased only slightly, while the maximum torque (MH) increased gradually, with increase in NR/CS/PHB content; thescorching tendency of NR/CS/PHB compounds increased with the increase in CS/PHB content; the optimum cure time (t90) decreased firstly, then increased with increase in CS/PHB content, and was not greatly different from that of NR compound. The results of mechanical properties of NR/CS/PHB vulcanizates showed that the tensile strength and elongation at break deceased, whereas the 300% and 500% moduli, tear strength and hardness increased, with increase in CS/PHB content.
Synthesis and Application of a Novel Intumescent Flame Retardant Containing Ferrocenyl
Authors: Chen Cong Yan , Fan Rui Lan , Yun Guan Qun
Published: October 2014

A novel intumescent flame retardant (IFR) containing ferrocene and caged bicyclic phosphate groups, 1-oxo-4-[4'-(ferrocene carboxylic acid phenyl ester)] amide-2, 6, 7-trioxa-1-phosphabicyclo- [2.2.2] octane (PFAM), was successfully synthesized. The synthesized PFAM were added to flammable polyurethane (PU) as flame retardants and smoke suppressants. The structure of PFAM was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR) and elemental analysis. Thermal stability of PFAM was tested by themogravimetric analysis (TGA). The results revealed that PFAM had good thermal stability and high char weight, the char weight up to 54% at 600 °C. Flammability properties of PU/PFAM composites were investigated by limiting oxygen index (LOI) test and UL-94 test, respectively. The results of LOI tests showed that the addition of PFAM enhanced flame retardancy of PU. When the content of PFAM reaches to 3%, the LOI value is 22.2. The morphologies of the char for PU and PU/3% PFAM composite can be obtained after LOI testing were examined by SEM. The results demonstrated that PFAM could promote to form the compact and dense intumescent char layer. Experiments showed that, the PFAM application of polyurethane showed positive effect.
Effect of Templates on Catalytic Activity of Ordered Mesoporous Ceria for CO Oxidation
Authors: Yang Peng , Zhou Shi Yu , Lei Jia Heng
Published: October 2014

Mesoporous ceria catalysts were prepared by nanocasting of a mesoporous carbon and KIT-6. The prepared mesoporous ceria catalysts were used to catalyze CO oxidation. The various characterization techniques were employed to study the relationship between catalyst nature and catalytic properties. The results indicate that ceria prepared by using mesoporous carbon as template possess an ordered mesoporous architecture and exhibit much better catalytic activity compared with those prepared by using KIT-6 as template. The residual SiO2from KIT-6 was demonstrated to be the main reason for the much worse catalytic activities by the characterization results of X-ray Fluorescence Spectrometer and FTIR spectra.
In-Suit Synthesis (ZrB2-SiC)/Si High Temperature Oxidation Resistance Coating by Argon Arc Cladding
Authors: Wang Zhen Ting , Zhu Shi Kui
Published: October 2014

In order to overcome the occurrence of insufficient oxidation reaction, high temperature oxidation resistance (ZrB2-SiC)/Si composite coating was fabricated on the surface of graphite electrode by argon arc cladding, process using the Si, Zr and B4C power blends. The microstructure and phase composition of the clad layer were researched by means of scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). The result shows that the coating consist of ZrB2 and SiC particles, The combination of the cladding layer and the graphite matrix results in kind of a continuous interface without visible defects. As the result of burning 60 min at 1573K, the oxidation weightlessness rate is 0.62%.
Mechanical Response of T300/BMP350 Composites under Tensile Loading at Room and Elevated Temperatures
Authors: Zhou Ping , Jia Pu Rong , Pan Wen Ge
Published: October 2014

In this paper, the effect of elevated temperature on the behavior of carbon fiber-reinforced T300/BMP350 unidirectional laminates was studied by loading static tensile on 0°, 90°and ±45° lay-up. The stress-strain relationships of the laminates under different temperatures were obtained. The effect of temperature on the mechanical properties of materials was systematically studied. The damage and failure mechanisms of the material were studied by analyzing the material stress-strain curves and the failure modes. Results show that the T300/BMP350 polyimide matrix composites have a strong resistance to high temperature. For 0° and 90° lay-up, the retentions of tensile strength and modulus are more than 80% and 50%, respectively. High temperature has little effect on the material failure modes. Finally, based on the test results, an empirical formula which relates strength and temperature of the material was fitted.
Fabrication and Phase Transition of Bi2O3-Doped Sr3Ti2O7 Ceramics
Authors: Yang Sheng Jie , Gao Feng , Qin Meng Jie , Zhang Chao Chao , Huang Xi Xi
Published: October 2014

Sr3Ti2O7ceramics with pure Ruddlesden-Popper phase (RP) were synthesized by conventional solid state method. The influences of the Bi2O3addition, the calcination temperature, and the sintering temperature on the phase transition were studied. The results showed that for the samples without doping Bi2O3, the main phase of calcined powders is Sr3Ti2O7, but pure Sr3Ti2O7phase cannot be obtained in the sintered ceramics because of the Sr3Ti2O7decomposition. For the samples doping with Bi2O3, although the main phase of the calcined powder is SrTiO3, the single RP phase Sr3Ti2O7can be obtained after sintering, which should be attributed to the formation of Sr3Bi2O6phase during calcination stage. Bi2O3addition is beneficial to the formation of the Sr3Ti2O7RP phase.
Peak Diffusing Measurement Method for Estimating Thermal Diffusivity of Thin Films
Authors: Dong Hui Long , Zheng Bo Yu , Chen Fei Fan
Published: October 2014

A novel peak diffusing measurement method is reported. In this method, a pulsed Gaussian heat source is focused on the material’s surface, and a thermal camera is utilized for detecting the temperature evolution. Specially, the peak temperature timetmaxat different distance from the heat source center is extracted using the Singular Spectrum Analysis (SSA). Thermal diffusivity is then calculated by fitting multiple sets of extractedtmaxinto the derived regression equation. The advantage of this method is that it does not require the high precision time synchronization between the excitation source and detector. Also, the calculation process is very simple, which achieves an efficient in situ measurement of the thermal diffusivity. The measured radial thermal diffusivity of samples prepared from Ti and Ni is in good agreement with the reference data with a 1.8% and a 3.9% error bound.
A Novel Extraction-Cleanup Method for Determination of Trace PPCPs in Water Samples
Authors: Jiao Zhe , Chen Hong Wei , Zhang Su Ling
Published: October 2014

In this contribution, a simple and sensitive extraction-cleanup method which was termed MAE-μ-SPE, was developed for the analysis of pharmaceutical and personal care products (PPCPs) in environmental water samples. The PPCPs included bisphenol A (BPA), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP), tetracycline (TC), deoxytetracycline (DC), oxytetracycline (OTC) and chloroteracycline (CTC). In this method, the PPCPs in the samples were extracted by microwave-assisted extraction (MAE) following adsorbed by copper (II) isonicotinate in micro-solid phase extraction (μ-SPE) device. The PPCPs were determined by high performance liquid chromatography with ultra-violet detector (HPLC-UV). The procedure of the MAE-μ-SPE was optimized in extraction temperature, extraction time, desorption time and desorption solvent. Analytical performances, such as limits of detection (in the range of 2.0-8.5 μg/L), quantification (in the range of 6.6-28.0 μg/L), and repeatability of the over-all procedure (less than 13%) were established. DEP, DBP, DEHP and TC studied in water samples were ranged from 18.2-68.8 μg L-1, while BPA, OTC, CTC and DC were found all below the detection limit in these samples.
Experimental Investigation on Mechanical Properties of Sandstone in Three Gorges Reservoir Area under Unloading Condition
Authors: Wang Xing Xia , Huang Jian Wen , Liao Zai Yi
Published: October 2014

Test results show that unloading failure is more brittle than loading failure, and rock samples suffer more damage under unloading failure, especially in high stress. Unloading failure leads to deterioration of deformation modulus, internal friction angle, and cohesion, whose values changes with the changing of stress state. Unloading stress-strain curves of sandstone samples could be divided into four stages, loading stage, unloading stage, brittle stress drop stage, ideal plastic stage, and well fitted by polynomials. There is springback deformation in the second stage, which decreases with increase of initial confining pressure. These test results could offer theory support for analysis of deformation and stability of actual projects.
Prediction of Hybrid Fiber Reinforced Concrete Strength on Base of RBF & BP
Authors: Li Nan , Zhao Jun Hai , Wang Juan , Zhu Qian
Published: October 2014

The complex nonlinear problem exists between the factors which influence the strength of hybrid fiber reinforced concrete. The nonlinear relationship between input variables as the factors and output variables as the strength can be obtained artificial neural network which have the feature of self-adapting, self-studying and nonlinear mapping. RBF and BP neural network models are established in MATLAB in this paper based on experimental values. Compressive strength and flexural strength of hybrid fiber reinforced concrete are predicted respectively and comparing with the measured values, predicted values are analyzed. The results show that the predicted values based on RBF tally with the experimental values, and the strength prediction ability of RBF is higher than BP neural network. The needs of engineering can be meet by this method with accurate prediction ability, a new method for the study of hybrid fiber reinforced concrete strength is provided.
Failure Analysis on the Collapsed Tubing of High Pressure and High Production Gas Well in the Process of Testing and Production
Authors: Xue Ji Jun , Zhao Bin , Zhao He
Published: October 2014

The split, fall, collapse and severe diapirism of tube body happened on one of the tubing used in the gas well of high pressure and high production in the process of the trial extraction. This paper aims to explore the reason of its occurrence through the research of the macroscopic analysis, mechanical and chemical property test and microscopic metallographic test study. The result of the research shows that the multiphase flow of gas, liquid and solid in the tubing may produced an instantaneous negative pressure and increased the possibility of the tubing being collapsed in the process of gas testing and production.Then it resulted in clogging, severe ablation, thinning wall and piercing in tube and finally the tube broke because of the low tensile strength.