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Journal of Ocean University of China 2021年第6期20卷 1451-1458页

作者： YAN Xia shi xiaofeng MA Jun Optics and Optoelectronics Laboratory of Qingdao Ocean University of ChinaQingdao 266100China

To realize the fast and accurate quantitative analysis of the mixture of polycyclic aromatic hydrocarbons(PAHs),surface-enhanced Raman spectroscopy(SERS)coupled with multivariate calibrations were *** this study,three kinds of calibration algorithms were used to quantitative analysis of the mixture of naphthalene(Nap),phenanthrene(Phe),and pyrene(Pyr).Firstly,partial least squares(PLS)algorithm was used to select characteristic variables,then the global search capability of genetic algorithm(GA)was used for the determining of the initial weights and thresholds of back propagation(BP)neural network so that local minima was *** PLS-GA-BP model exhibited superiority to quantify PAHs mixture,which achieved R2=0.9975,0.9710,0.9643,ARE=10.07%,19.28%,16.72%and RMSE=13.10,5.40,5.10 nmol L−1 for Nap,Phe,Pyr(in the PAHs mixture)concentration prediction *** forecast error,ARE and RMSE have been reduced more than 50%and 60%respectively compared with the whole spectral BP *** study indicates that accurate quantitative spectroscopic analysis of the mixture of PAHs samples can be achieved through the combination of SERS technique and PLS-GA-BP algorithm.

关键词： polycyclic aromatic hydrocarbons(PAHs) surface enhanced Raman spectral(SERS) back propagation(BP)algorithm multi-component quantitative analysis

Chiral pillar[n]arenes:Conformation inversion,material preparation and applications

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Chinese Chemical Letters 2022年第8期33卷 3613-3622页

作者： Chengxiang shi Hui Li xiaofeng shi Liang Zhao Hongdeng Qiu CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Department of Gansu Provincial Cancer Hospital Institute of Materia MedicaLanzhou 730000China College of Chemistry Zhengzhou UniversityZhengzhou 450001China College of Chemistry and Chemical Engineering Gannan Normal UniversityGanzhou 341000China

Chiral pillar[n]arenes have shown great research value and application prospect in construction of chiral materials and chiral applications,due to their inherent planar chiral configurations,chiral recognition ability,easy modification and highly symmetric hydrophobic *** review systematically summarized the conformation inversion factors of planar chiral pillar[5]arenes(pR/p S),such as solvents,temperature,substituent size,alkyl chains,chiral and achiral guest *** firstly introduced the applications of chiral pillar[n]arenes for constructing chiral materials and pointed out that planar conformation inversion showed a great potential role in constructing chiral ***,we mainly concluded the chiral applications of chiral and planar chiral pillar[n]arenes like chiral enantiomer analysis by circular dichroism,electrochemistry or chiral fluorescence *** this review,we found that the inherent planar chiral conformation of chiral pillar[n]arenes have played a very important role in chiral field in the future.

关键词： Chiral pillar[n]arene Planar chiral configuration Chiral supramolecular materials Chiral separation and analysis Conformation inversion

Integrated System for Combined Optical Coherence Tomography-Raman Spectroscopy of Neocaridina denticulate sinensis

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Journal of Ocean University of China 2021年第1期20卷 94-100页

作者： LIU Xiaoying ZHANG Xu MA Jun shi xiaofeng Optics and Optoelectronics Laboratory Ocean University of ChinaQingdao 266100China

Optical coherence tomography(OCT)and Raman spectroscopy(RS)can be complementary biological tissue optical analysis *** study the internal structure and tissue compositions of biological samples,an OCT-RS system was built to carry out OCT section imaging and RS analysis in *** denticulate sinensis were collected regularly for morphological observation by OCT imaging and biochemical investigation based on the Raman *** internal structure of the *** sinensis was imaged by OCT,and the morphology of the tissues and the position in the body were distinguished according to the gray scale *** imaging depth along the vertical direction of Z-axis in *** sinensis is about 1.60 *** detection was selectively performed based on the OCT *** main Raman peaks of the rostrum,the cephalothorax,the abdominal segment,and the telson section are at 1006,1156,1447,1491 and 1515 cm-1,which are identified as proteins and amino *** presence of 1497 cm-1 at the cephalothorax is different from other parts,probably due to the presence of organs such as ovary,whose compositions are different from those of other *** combination of optical coherence tomography and Raman spectroscopy can provide information about morphological and biochemical features of tissues,and has potential applications in biomedical detection and imaging.

关键词： optical coherence tomography(OCT) Raman spectroscopy(RS) Neocaridina denticulate sinensis biological tissue

Low-mature gases and their resource potentiality

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Chinese Journal Of Geochemistry 2009年第3期28卷 231-238页

作者： XU Yongchang WANG xiaofeng shi Baoguang The Key Laboratory of Gas Geochemistry Chinese Academy of Sciences Lanzhou 730000 China

In the 80’s of last century, based on the advances in natural gas exploration practice, the concepts of bio-thermocatalytic transitional-zone gas and early thermogenetic gas were proposed, and the lower limit Ro values for the formation and accumulation of thermogenetic natural gases of industrial importance have been extended to 0.3%–0.4%. In accordance with the two-stage model established on the basis of carbon isotope fractionation involved in the formation of coal-type natural gases, the upper limit Ro values of lowly evolved natural gases should be set at 0.8%–1.0%. This is the concept of low-mature gas which is commonly accepted at the present time. The Urengoy super-large gas field in western Siberian Basin is a typical example of low-mature gas field, where low-mature gas reserves account for 20% of the globally proven natural gas reserves, and this fully indicates the importance of this kind of resources. The proven reserves of natural gases in the Turpan-Hami Basin of China are approximate to 1000×108 m3, and the thermal evolution indices of source rocks are Ro=0.4%–0.8%. The δ13C1 values of methane are mainly within the range of -44‰– -39‰ (corresponding to Ro=0.6%–0.8%), and those of ethane are mainly within the range of -29‰– -26‰, indicating that these natural gases should be designated to the coal-type low-mature gases. The light hydrocarbon evolution indices of natural gases also provide strong evidence suggesting that they are the coal-type low-mature gases. If so, low-mature gas in the Turpan-Hami Basin has been accumulated to such an extent as to be equivalent to the total reserves of three large-sized gas fields, and their existence is of great significance in the study and exploration of China’s low-mature gases. If it is evidenced that the source rocks of low-mature gases are related mainly to coal measures, China’s abundant lowly evolved coal series resources will provide a huge resource potentiality for the generation of low-mature gases.

关键词：资源潜力低成熟气体

DETERMINATION OF CLOSURE EFFECT IN FATIGUE CRACKING BY MEANS OF COMPLIANCE TECHNIQUE AND NUMERICAL METHOD

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Acta Metallurgica Sinica(English Letters) 1992年第1期5卷 38-42页

作者： Cheng, Yuren shi, xiaofeng Peng, Xiang Hou, Binglin Northern Jiaotong Univ Beijing China

The crack tip strain gauge method in the compliance technique was used to determine the opening load of notched crack of axle steel,and the nonlinear finite element ADINA program, to which the cyclic stress-strain curve of axle steel was applied,was used to analyze the stress-strain field ahead of the crack tip and the opening load of notched *** results of both the compliance technique and the numerical method were in good *** this pa- per,the concept of the sensitive point is proposed and the key to the determination of the crack opening load in the experiment is to place a strain gauge at sensitive *** is certified by both experimental and numerical methods that the sensitive point has the best linear relation- ship character and the value of strain is much greater.

关键词： crack closure effect compliance technique numerical method axle steel

Change in coral reef benthic communities in the Lembeh Strait and Likupang, North Sulawesi, Indonesia

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Acta Oceanologica Sinica 2018年第12期37卷 45-54页

作者： HADI Tri Aryono SIHOUKA Jimmy shi xiaofeng BUDIYANTO Agus SUHARSONO Research Center for Oceanography Indonesian Institute of Sciences Conservation Unit for Bitung Marine Life Indonesian Institute of Sciences Third Institute of Oceanography Ministry of Natural Resources

Anthropogenic impacts and natural disturbances have been intense recently in the global scale, affecting the composition of coral reef benthic communities from coral to algal dominated reefs. However, this condition does not always occur considering corals are able to recover when the stressors falter. This study aims to investigate the change in coral reef benthic communities and the relationship among benthic categories. The study was carried out in 2014 and 2016 at five sites, three sites in the Lembeh Strait and two sites in Likupang, North Sulawesi Province. Underwater Photo Transect(UPT) was used at depth of around 4–6 m in slope areas. The result indicated that the benthic communities were slightly changing: the percent covers of hard corals, sponges, soft corals, macroalgae and substrate categories were not significantly different between the years but category of others, particularly seasonally growing hydroid, increased significantly, occupying the available substrates and overtopping other benthos surrounding. The study also found that there was a significant relationship between the change in benthic gradient and the number of hard coral colonies: when the composition becomes less complex, the number of colony declines. In contrast, the hard coral diversity remained unchanged, suggesting the coral reefs apparently have an ecological resilience(sustainable species diversity) against the change although ecological complexity declines. In addition, the hard coral cover was significantly correlated with soft coral and sponge covers, which did not change significantly among the years. In general, the coral reefs in North Sulawesi might experience a temporary blip due to the increasing percent cover of others, and be predicted to recover as there was no indication of soft corals and sponges to increase significantly. However, it is necessary to investigate the dynamic of benthic communities in different depth gradients to gain a comprehensive understanding as

关键词： coral reef benthic community percent cover Lembeh Strait Likupang

Design of MCI single and symmetrical on-chip spiral inductors

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Journal of Semiconductors 2017年第6期38卷 88-92页

作者： Bo Han shibing Wang xiaofeng shi School of Computer and Information Engineering Fuyang Teachers College Department of Electronic Science and Technology University of Science and Technology of China

In this paper,the MCI（multipath crossover interconnection）technique for octagon single and symmetrical spiral inductors has been presented to improve the quality *** metal wires of the single and symmetrical inductors formed by the top metal are divided into multiple segments according to the depth of the skin *** outermost path of the metal is crossover-interconnected to the innermost path by the underlayer metal and via The crossover technique makes the lengths of the total current paths between two ports approximately equal to each ***,the induced magnetic flux and resistance of each path can be balanced and the Q-factor of spiral inductors can be *** proposed MCI technique has been validated by the electromagnetic simulation with the 130-nm 1P6M SiGe BiCMOS *** the devices with occupying areas of 240 240 μm^2,results of electromagnetic simulation show that about 24%improvement in the Q-peak（3.3 GHz）of the MCI single inductor as compared to conventional single inductors（3.1 GHz）,and about 88.1%improvement in the Q-peak（3.2 GHz）of the MCI symmetrical inductor as compared to conventional symmetrical inductors（1.8 GHz）.

关键词： crossover interconnection spiral inductor high Q-factor current crowding effect skin effect

Carbon and hydrogen isotopic composition and generation pathway of biogenic gas in China

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Chinese Journal Of Geochemistry 2009年第2期28卷 119-124页

作者： SHEN Ping WANG xiaofeng XU Yin shi Baoguang XUYongchang The Key Laboratory of Gas Geochemistry Chinese Academy of Sciences Lanzhou 730000 China

The carbon and hydrogen isotopic composition of biogenic gas is of great importance for the study of its generation pathway and reservoiring characteristics. In this paper, the formation pathways and reservoiring characteristics of biogenic gas reservoirs in China are described in terms of the carbon and hydrogen isotopic compositions of 31 gas samples from 10 biogenic gas reservoirs. The study shows that the hydrogen isotopic compositions of these biogenic gas reservoirs can be divided into three intervals: δDCH4>-200‰,-250‰<δDCH4<-200‰ and δDCH4<-250‰. The forerunners believed that the main generation pathway of biogenic gas under the condition of continental fresh water is acetic fermentation. Our research results showed that the generation pathway of biogenic gas under the condition of marine facies is typical CO2-reduction, the biogenic gas has heavy hydrogen isotopic composition: its δDCH4 values are higher than-200‰; that the biogenic gas under the condition of continental facies also was generated by the same way, but its hydrogen isotopic composition is lighter than that of biogenetic gas generated under typical marine facies condition: -250‰<δDCH4<-200‰, the δDCH4 values may be related to the salinity of the water medium in ancient lakes. From the relevant data of the Qaidam Basin, it can be seen that the hydrogen isotopic composition of biogenic methane has the same variation trend with increasing salinity of water medium. There are biogenic gas reservoirs formed in transitional regions under the condition of continental facies. These gas reservoirs resulted from both CO2-reduction and acetic fermentation, the formation of which may be related to the non-variant salinity of ancient water medium and the relatively high geothermal gradient, as is the case encountered in the Baoshan Basin. The biogenic gas generating in these regions has light hydrogen isotopic composition: δDCH4<-250‰, and relatively heavy carbon isotopic composition. There is a fairly stro

关键词：碳同位素组成生物气藏二氧化碳重氢中国气藏描述醋酸发酵古水介质

Structural, electronic, and optical absorption properties of TiO_2 nanotube adsorbed with Cu_n clusters

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Science China(Physics,Mechanics & Astronomy) 2014年第8期57卷 1519-1525页

作者： GAO YanLin LI XiuYan shi xiaofeng YANG Zhi XU LiChun LIU RuiPing College of Physics and Optoelectronics Taiyuan University of Technology

The structural, electronic, and optical absorption properties of TiO2 nanotube （TiO2NT） with Cun clusters （n =1-4） adsorbed on its surface have been investigated based on density functional theory calculations. The TiO2NT is constructed by rolling up a （101） sheet of anatase TiO2 around the [ 1-01 ] direction; the ground states of Cun/TiOzNT systems are determined by analyzing the average adsorption energies. Calculation results show that odd-even oscillations occur for the average adsorption energy, the Cu-O bond length, and the amount of transferred electrons, with the increase in Cu. cluster size; and the Cun/TiO2NTs with odd n＇s demonstrate stronger interaction between the Cu. cluster and the TiO2NT. Also, the impurity states introduced by the Cun cluster to the band gap of TiOzNT cause an obvious redshift of the optical absorption spectrum toward the visible light region, especially for the even n cases.

关键词： TiO2 nanotube Cun cluster electronic structure optical absorption property

Highly efficient removal of trace lead(Ⅱ)from wastewater by 1,4-dicarboxybenzene modified Fe/Co metal organic nanosheets

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Journal of Materials Science & Technology 2022年第3期98卷 212-218页

作者： Junmao Hong Le Kang xiaofeng shi Renbo Wei Xianmin Mai Duo Pan Nithesh Naik Zhanhu Guo School of Environment and Safety Engineering School of Materials Science and TechnologyInstitute of Advanced Energy Materials and SystemsNorth University of ChinaTaiyuanChina School of Chemical Engineering Northwest UniversityXi’an 710069China School of Urban Planning and Architecture Southwest Minzu UniversityChengdu 610041China Key Laboratory of Materials Processing and Mold(Zhengzhou University) National Engineering Research Center for Advanced Polymer Processing TechnologyMinistry of EducationZhengzhou UniversityZhengzhou 450000China Department of Mechanical&Manufacturing Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnataka 576104India Integrated Composites Laboratory(ICL) Department of Chemical&Biomolecular EngineeringUniversity of TennesseeKnoxvilleTN 37996United States

A novel Fe/Co metal organic complex nanosheet modified by 1,4-dicarboxybenzene(BDC),i.e.,FeCo@BDC,was prepared,and highly efficient removal performance for trace lead(Ⅱ)(Pb^(2+))was demonstrated in the neutral aqueous *** removal rates were higher than 95%and the adsorption was equilibrated in 15 *** isotherms and kinetics for the adsorption Pb^(2+)by the FeCo@BDC adsorbents followed Langmuir model and pseudo-second-order model,*** maximum adsorption capacity was 220.48 mg g^(-1).The FeCo@BDC adsorbents also own a prominent regeneration *** prominent performance of in the removal of trace Pb^(2+)makes FeCo@BDC an ideal candidate as commercial adsorbent materials.

关键词： Metal organic complex Nanosheet Trace level Lead(Ⅱ) Adsorption