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Tungsten 2024年第4期6卷 778-793页

作者： Peng-Fei Dai yang Zhang Sergey Rogozhkin Ji-Hong Han Shu-wen Li Zhong-Wu Zhang Key Laboratory of Superlight Materials and Surface technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University National Research Nuclear university “MEPh I” National Research Center “Kurchatov Institute”

This study investigated the effect of Nb-content on the corrosion behavior of the Al7Cr20Fe3.-xNi3.Mo3.bx（x=0,1 and 2）high-entropy alloys in a *** results indicated that only the face centered cubic phase existed in the NbO and Nbl alloys,while the emergence of Laves phase was observed when Nb-content reached 2 at.%.The NbO and Nb1alloys exhibited pitting corrosion,while the NiAl-rich phase experienced localized preferential corrosion in the Nb2 *** electrochemical results revealed that the corrosion current density of the Nbx（x=0,1 and 2） alloys fell within the range of 10-8-10-7A·cm-2,with a pitting corrosion potential exceeding 700 ***,the Nb1 alloy exhibited the most impressive corrosion resistance,as its corrosion current density(7 × 10-8A·cm-2) was merely half that of 3.6LN stainless *** is attributed to its rapid passivation process,resulting in the development of a protective film characterized by an increased Cr2O3.Al2O3.Cr（OH）*** study highlighted that the addition of Nb contributed to gram refinement,decreased corrosion current density,and elevated pitting potential,favoring passivation and improving corrosion ***,excessive Nb-content resulted in the emergence of the Laves phase,inducing galvanic corrosion and diminishing resistance to corrosion.

关键词： Corrosion High entropy alloys Microstructure Niobium Passive film

Changes in physicochemical characteristics of wheat flour and quality of fresh wet noodles induced by microwave treatment

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Grain & Oil science and technology 2024年第3期7卷 177-185页

作者： Jian Zhang Xuejie Li Xiujuan Ren Yanxia An Xiaoyan Song yang Zhao Yaqing wen Weifeng Zhang college of Food science and technology Henan Agricultural UniversityZhengzhou 450000Henan ProvinceChina School of Food science and Engineering Zhengzhou University of Science and TechnologyZhengzhou 450064Henan ProvinceChina

Fresh wet noodles(FWN) are popular staple foods due to its unique chewy texture and favorable taste. However,the development of FWN is limited by its short shelf life and high browning rate. It has been found that the quantity of original microorganisms in wheat flour produced by traditional method is relatively high, which is detrimental to the processing quality and storage stability of FWN. Consequently, it becomes imperative to decrease microorganisms in wheat flour. Microwave treatment has been regarded as a promising method in the food industry due to its potential in inhibiting microbial growth and inactivating enzymes without causing adverse effect on the food quality. This study aims to investigate the effects of microwave treatment of wheat kernels under different powers(1, 2, 3. 4, 5 kW) on the physicochemical properties of wheat flour and the quality of FWN. The results revealed that microwave treatment had a significant effect on microbial inhibition and enzyme inactivation, wherein the total plate count(TPC) and yeast and mold counts(YMC) decreased by 0.87 lg(CFU/g) and 1.13.lg(CFU/g) respectively, and PPO activity decreased from 11.40 U to 6.3. U. The dough quality properties, such as stability, extensibility, and starch viscosity, improved significantly under different microwave conditions. Confocal laser scanning microscopy(CLSM) images indicated that starch and proteins aggregated gradually in treated flour, altering rheological properties of dough. From the results of scanning electron microscopy(SEM), microwave treatment led to the appearance of disrupted structure in the gluten proteins, but the secondary structure of proteins altered slightly. Rheological properties of dough confirmed that the microwave treatment greatly affected processing characteristics of wheat flour products, with significant advantageous consequences on product quality, especially for textural properties of FWN. Furthermore, FWN darkening could be inhibited noticeably aft

关键词： Microwave treatment Sterilization Confocal laser scanning microscopy Rheological properties Protein structures

Thermodynamic database of the phase diagrams in the Mg-Al-Zn-Y-Ce system

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Rare Metals 2006年第5期25卷 441-447页

作者： LIU Xingjun WANG Cuiping wen Mingzhong CHEN Xing PAN Fusheng Department of Materials science and Engineering Xiamen University Xiamen 361005 China college of Materials science and Engineering Chongqing University Chongqing 400045 China

The Mg-Al-Zn-Y-Ce system is one of the key systems for designing high-strength Mg alloys. The purpose of the present article is to develop a thermodynamic database for the Mg-Al-Zn-Y-Ce multicomponent system to design Mg alloys using the calculation of phase diagrams （CALPHAD） method, where the Gibbs energies of solution phases such as liquid, fcc, bcc, and hcp phases were described by the subregular solution model, whereas those of all the compounds were described by the sublattice model. The thermodynamic parameters describing Gibbs energies of the different phases in this database were evaluated by fitting the experimental data for phase equilibria and thermodynamic properties. On the basis of this database, a lot of information concerning stable and metastable phase equilibria of isothermal and vertical sections, molar fractions of constituent phases, the liquidus projection, etc., can be predicted. This database is expected to play an important role in the design of Mg alloys.

关键词： thermodynamic database CALPHAD method phase diagram Mg-Al-Zn-Y-Ce system magnesium alloys

The Optical Variability Properties of TeV Blazars

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Research in Astronomy and Astrophysics 2024年第9期24卷 66-75页

作者： Zi-An Su wen-Xin yang Xiang-Tao Zeng Le-Jian Ou Ze-Lin Li Jiang-He yang Jun-Hui Fan Department of Physics School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Greater Bay Brand Center of the National Astronomical Data Center Guangzhou 510006China Astronomy science and technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China college of Microelectronics Feicuihu Campus of Hefei University of TechnologyHefei 230601China college of Mathematics and Physics science Hunan University of Arts and ScienceChangde 415000China

Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability,although this kind of association is unclear *** this work,we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale,the brightness-dependent spectral property,the correlation between the the brightness variation and the polarization,and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 20 TeV *** analyses arrive at the following results:(1)The largest variation amplitude in R-band,ΔR_(M),covers a range from ΔR_(M)=0.29 mag(1ES 23.4+514)to ΔR_(M)=4.66 mag(3. 279).(2)Intra-day variability was found from five sources with timescales from 0.14 day for S50716+714 to 0.98 day for PKS *** sources show spectra that are bluer when they become brighter,suggesting a common bluer-when-brighter property.(3.The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization.(4)The largest polarization is correlated with the largest optical variation,suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3. Hong-Ning WANG~(2,1*) Xin PAN~4 Tao XIE~1 Qi WU~5 Zi-wen XIE~1 Wan-Rong ZHOU~1 1 Laboratory of Veterinary and Biotechnology,Sichuan Agricultural university,Ya'an 625014,{3. 2 Sichuan university Bioengineering Research Center for Animal Disease Prevention and Control,Chengdu 610065,{3. 3.Faculty of Environment and Resource of Dujiangyan Campus,Sichuan Agricultural university,Dujiangyan 61183.,{3. 4 college of Earth science,Chengd university of technology,Chengdu 610059,{3. 5 college of Life science,Sichuan Agricultural university,Ya'an 625014,{3. Laboratory of Veterinary and Biotechnology Sichuan Agricultural University Ya'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5 U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5 *** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 51 *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42 *** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris

Enhanced direct gaseous CO_(2) fixation into higher bio-succinic acid production and selectivity

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Journal of Environmental sciences 2024年第9期143卷 164-175页

作者： Ziyi yang Wanling Wu Qing Zhao Irini Angelidaki Samuel Gyebi Arhin Dongliang Hua Yuxiao Zhao Hangyu Sun Guangqing Liu wen Wang Biomass Energy and Environmental Engineering Research Center Beijing University of Chemical TechnologyBeijing 100029China college of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Chemical and Biochemical Environmental Engineering Technical University of DenmarkDK-2800Kgs LyngbyDenmark Energy Research Institute Qilu University of Technology(Shandong Academy of Sciences)Shandong Provincial Key Laboratory of Biomass Gasification TechnologyJinan 250014China

Utilizing CO_(2)for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling(CCR)with simultaneous production of a useful platform *** succinogenes and Basfia succiniciproducens were selected and investigated as microbial ***,the type and concentration of inorganic carbon concentration and glucose concentration were evaluated.6 g C/L MgCO_(3.and 24 g C/L glucose were found to be the optimal basic operational conditions,with succinic acid production and carbon yield of over 3. g/L and over 40%,***,for maximum gaseous CO_(2)fixation,carbonate was replaced with CO_(2)at different ***“less carbonate more CO_(2)”condition of the inorganic carbon source was set as carbonate:CO_(2)=1:9(based on the mass of carbon).This condition presented the highest availability of CO_(2)by well-balanced chemical reaction equilibrium and phase equilibrium,showing the best performance with regarding CO_(2)fixation(about 15 mg C/(L·hr)),with suppressed lactic acid *** to key enzymes analysis,the ratio of phosphoenolpyruvate carboxykinase to lactic dehydrogenase was enhanced at high ratios of gaseous CO_(2),which could promote glucose conversion through the succinic acid *** further increase gaseous CO_(2)fixation and succinic acid production and selectivity,stepwise CO_(2)addition was evaluated.50%-65%increase in inorganic carbon utilization was obtained coupled with 20%-3.%increase in succinic acid *** was due to the promotion of the succinic acid branch of the glucose metabolism,while suppressing the pyruvate branch,along with the inhibition on the conversion from glucose to lactic acid.

关键词： Succinic acid CO_(2) fixation Actinobacillus succinogenes Basfia succiniciproducens Lactic acid

Study on Ceramic Cutting by Plasma Arc

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厦门大学学报（自然科学版） 2002年第S1期41卷 55-56页

作者： XU wen-ji 1, FANG Jian-cheng 2, LU Yi-shen 1 (1. School of Mechanical Engineering, Dalian university of technology, Dalian 116023.{3. 2. college of Mechanical Engineering and Automation, Huaqiao university, Quanzhou 3.2011,{3.)

Engineering ceramics are typical difficult-to-machine materials because of high hardness and brittleness. PAC (Plasma Arc Cutting) is a very important thermal cutting process and has been successfully used in cutting stainless steel and other difficult-to-machine alloys. PAC’s application in cutting ceramics, however, is still limited because the most ceramics are not good electronic conducts, and transferred plasma arc cannot be produced between cathode and work-piece. So we presented a method of plasma arc cutting engineering ceramics with additional anode. To reduce the kerf width and to improve the kerf quality, the hydro-magnetically confined plasma arc is used to cut engineering ceramic plates. By experiments and analyses the mechanism and characteristics of hydro-magnetic confined plasma are discussed and the effects of secondary confinement on cutting quality, arc properties, and optimal process parameters are presented. When the nozzle diameter is 3.mm, the kerf width of the Al 2O 3.ceramic plate with 6 mm thickness is less than 4.6 mm, and the cutting speed reaches to 0.9～1.2 m/min. Both theoretical analysis and experimental results have proved the feasibility and validity of the newly advanced hydro-magnetic plasma arc cutting, and the following conclusion can be drawn: (1)Synthesizing the advantages of both the water-constriction and magnetic constriction, the hydro-magnetic constriction of plasma arc forms a three-dimensional constriction with improved shape and uniformity of arc column, narrower kerfs, minimal beveling of cuts and higher dross-free cutting speeds than those under either water-constriction or magnetic constriction alone.(2)Hydro-magnetic constriction is capable of improving arc stability, which is reflected in the higher arc voltage at which arc-extinction occurs, than that under any single constriction. (3.For a given diameter of nozzle, quality cut can be produced by using a lower arc current than usually required in conventional plas

关键词： plasma cutting engineering ceramic plasma confinement

Fault tolerant quantum secret sharing against collective-amplitude-damping noise

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science china(Physics,Mechanics & Astronomy) 2011年第9期54卷 1619-1624页

作者： yang yuguang CHAI HaiPing WANG Yuan TENG YiWei wen {3. college of Computer science and technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi'an 710071 China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing 100876 China

We present a quantum secret sharing protocol against collective-amplitude-damping noise. Each logical qubit is encoded in two qubit noiseless states. So it can function over such a noisy channel. The two agents encode their messages on each logical qubit only by performing a permutation operation on two physical qubits. Although each logical qubit received by each agent only carries a bit of information, the boss Alice can read out her agents' information by discriminating two orthogonal states by performing single-qubit measurements assisted by local operation and classical communication (LOCC).

关键词： quantum secret sharing fault tolerant collective noise amplitude damping

Giant panda(Ailuropoda melanoleuca)neonates use broadband calls to communicate with their mothers

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Integrative Zoology 2024年第2期19卷 277-287页

作者： Lin ZHAO Jianbin CHENG wen ZENG Bo yang Guiquan ZHANG Desheng LI Hemin ZHANG Christina DBUESCHING Dingzhen LIU Ministry of Education Key Laboratory of Biodiversity Science and Ecological EngineeringCollege of Life SciencesBeijing Normal UniversityBeijingChina Key Laboratory of State Forestry and Grassland Administration on Conservation Biology of Rare Animals in The Giant Panda National Park China Conservation and Research Center for the Giant PandaDujiangyanSichuan611830China Department of Biology Irving K.Barber Faculty of ScienceUniversity of British ColumbiaOkanaganKelownaBritish ColumbiaCanada

Infant call structure should have evolved to elicit maximum maternal attention and *** of giant pandas produce three types of vocalizations reported to be vitally important in the context of mother–infant ***,how cubs,0–15 days old,communicate with their mothers to elicit maternal care remains *** analyzed 12 different call parameters of 3.75 squawks,13.5 squalls,and 491 croaks from 11 captive giant panda(Ailuropoda melanoleuca)neonates from age 0 to 15 *** playback experiments,we also tested whether mothers could detect *** results show that neonates use broadband calls with ultrasonic frequencies up to 65 kHz to convey information about their physiological needs and to attract maternal *** playback experiments,we tested if mothers reacted differently to broadband calls(BBC)than to artificially altered calls that included only frequencies20 kHz(AUDC)or calls that included only frequencies>20 kHz(USC).Playback confirmed that,although adult females responded significantly less often to USC,BBC than to or AUDC,they could detect USC,BBC and generally made appropriate behavioral responses,indicating a potential benefit for neonates to utilize ultrasonic and broadband *** findings provide a new insight into mother–infant communication in giant pandas and will be helpful for reducing the mortality of cubs,younger than 1 month old,in captivity.

关键词： acoustic communication broadband calls maternal care neonates ultrasonic frequencies