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| 1 | New eolian red clay sequence on the western Chinese Loess Plateau linked to onset of Asian desertification about 25 Ma ago显示文摘The expansion of inland Asia deserts has considerably influenced the environmental, social and economic activities in Asia. Aridification of inland Asia, especially timing of the initiation of Asian desertification, is a contentious topic in paleoclimatology. Late Cenozoic eolian loess-red clay sequences on the Chinese Loess Plateau, which possess abundant paleoclimatic and paleo-environmental information, can be regarded as an indicator of inland Asia desertification. Here we present a detailed magnetostratigraphic investigation of a new red clay sequence about 654 m in Zhuanglang located at the western Chinese Loess Plateau. Sedimentological, geochemical, mineralogical, and quartz morphological lines of evidence show that the red clay is of eolian origin. Magnetostratigraphic correlations indicate that this core sequence spans from 25.6 to 4.8 Ma, and typical eolian red clay appears as early as 25 Ma. This extends the lower limit of the red clay on the Chinese Loess Plateau from the previously thought early Miocene back into the late Oligocene. This new red clay record further implies that the inland Asia desertification was initiated at least by the late Oligocene. This sequence provides a unique high-resolution geological record for understanding the inland Asia desertification process since the late Oligocene. | QIANG XiaoKe AN ZhiSheng SONG YouGui CHANG Hong SUN YouBin LIU WeiGuo AO Hong DONG JiBao FU ChaoFeng WU Feng LU FengYan CAI YanJun ZHOU WeiJian CAO JunJi XU XinWen AI Li | 2011 | Science China Earth Sciences2011，54，1： | 73 |
| 2 | Prediction of permafrost changes in Northeastern China under a changing climate显示文摘Northeastern China has the second largest expanse of permafrost in China,primarily known as Xing'an-Baikal permafrost.Located on the southeastern edges of the Eurasian cryolithozone,the permafrost is thermally unstable and ecologically sensitive to external changes.The combined impacts of climatic,environmental,and anthropogenic changes cause 3-dimensional degradation of the permafrost.To predict these changes on the southern limit and ground temperature of permafrost in Northeastern China,an equivalent latitude model (ELM) for the mean annual ground surface temperature (MAGSTs) was proposed,and further improved to take into account of the influences of vegetation and snow-cover based on observational data and using the SHAW model.Using the finite element method and assuming a climate warming rate of 0.048°C a-1,the ELM was combined with the unsteady-state heat conduction model to simulate permafrost temperatures at present,and to predict those after 50 and 100 a.The results indicate that at present,sporadic permafrost occurs in the zones with MAGSTs of 1.5°C or colder,and there would still be a significant presence of permafrost in the zones with the present MAGSTs of 0.5°C or colder after 50 a,and in those of-0.5°C or colder after 100 a.Furthermore,the total areal extent of permafrost would decrease from 2.57×105 km2 at present to 1.84×105 km2 after 50 a and to 1.29×105 km2 after 100 a,i.e.,a reduction of 28.4% and 49.8% in the permafrost area,respectively.Also the permafrost would degrade more substantially in the east than in the west.Regional warming and thinning of permafrost would also occur.The area of stable permafrost (mean annual ground temperature,or MAGT≤-1.0°C) would decrease from present 1.07×105 to 8.8×104 km2 after 50 a,and further decrease to 5.6×104 km2 after 100 a.As a result,the unstable permafrost and seasonally frozen ground would expand,and the southern limit of permafrost would shift significantly northwards.The changes in the permafrost environment may adversely affect on ecological environments and engineering infrastructures in cold regions.Avoidance of unnecessary anthropogenic changes in permafrost conditions is a practical approach to protect the permafrost environment. | WEI Zhi JIN HuiJun ZHANG JianMing YU ShaoPeng HAN XuJun JI YanJun HE RuiXia CHANG XiaoLi | 2011 | Science China Earth Sciences2011，54，6： | 15 |
| 3 | ELASTIC BEHAVIOR ANALYSIS OF 3D ANGLE-INTERLOCK WOVEN CERAMIC COMPOSITES显示文摘为 angle-interlockwoven 的有弹性的行为分析的一个微机械模型陶器的 composites 在这篇论文被建议。这个模型由在空间,在邻近的纱之间的洞和纱的实际剖面图几何学认为纤维是波动和连续性考虑实际织物结构。基于 laminate 理论,编织的 3D 角度联锁的有弹性的性质陶器的 composites 被预言。交叉的纬的不同数字几乎有一样的有弹性的 moduli。陶器的矩阵的厚度在有弹性的 moduli 上有小效果。当波动比率增加纵的模量减少和另外的幼仔的 moduli 增加时。在理论预言和试验性的结果之间的好同意在分析编织的 3Dangle-interlock 的有弹性的性质表明建议模型的可行性陶器的 composites。这篇论文的结果验证分析聚酯矩阵 composites 的方法对编织陶器的 composites 合适的事实。 | Chang Yanjun Jiao Guiqiong Wang Bo Liu Wei | 2006 | Acta Mechanica Solida Sinica2006，19，2： | 11 |
| 4 | A mechanically tuned Kerr comb in a dispersion-engineered silica microbubble resonator显示文摘This paper discusses the developement and investigation of a silica microbubble resonator(MBR) that is optimized to cancel mode dispersion with material dispersion, at a wavelength of approximately 1550 nm and maintain a quality factor of an optical mode as large as 5.4 × 10~7. Benefitting from the near-zero dispersion and high quality factor, a primary optical comb is generated in the MBR using cascaded four-wave mixing processes, which span over 300 nm with several tens of teeth. Furthermore, the frequency comb could be gradually tuned by mechanically stretching the MBR. This tunable Kerr comb has multiple potential applications in precision measurements and sensing applications, such as molecular spectroscopy and ranging. | FangJie Shu PeiJi Zhang YanJun Qian ZhengYu Wang Shuai Wan Chang Ling Zou GuangCan Guo ChunHua Dong | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，5： | 5 |
| 5 | Study on the Coincident-Loop Transient Electromagnetic Method in Seafloor Exploration——Taking Jiaodong Polymetallic Mine as a Model显示文摘The transient electromagnetic(TEM)method becomes more urgent than ever for marine ex-ploration due to abundant resource reserves and the increasing undersea engineering construction activities,especially in the offshore exploration of mineral deposits such as Sanshandao gold mine.However,the re-search and application of TEM method in marine environment are still challenged by many problems.Such contradiction motivates our study on the coincident-loop TEM in seafloor exploration.The TEM response of coincident loops is firstly derived in the integral form,based on the potential functions in Helmholtz equ-ations for a magnetic source locating in the whole-space layered model.The frequency-domain vertical magnetic field is described as the Hankel integral with double first-order Bessel functions of first kind.Se-condly,the time-domain induced voltage is obtained by transforming the frequency-domain response through the cosine transform and then taking the derivative of time.To simultaneously solve the Hankel transform and the cosine transform,a novel algorithm is introduced by adapting the fixed-point quadra-ture and extrapolation via the Shanks transformation.Finally,a typical conductivity model for marine po-lymetallic deposit is designed to investigate the characteristic of TEM response under various conditions.Numerical results demonstrate that existence of conductive seawater causes the TEM response to increase significantly and decay slower.The air-sea reflected electromagnetic waves lead to a significantly large fake negative response(NR)in shallower seawater with depth less than 300 m.Increase in the height of loops will weaken and delay the anomaly response and shorten the observation time-window.The height of configu-ration should be no more than 100 m for shallower targets and 50 m for deeper targets,respectively.The observation time-window should cover 10-1000 ms.Increase in the radius of loops only enhances the TEM response proportionally but hardly improves the relative anomaly.The vertical resolution on the low-resistivity target approximates 20 m for the configuration considered in the study.Decreases in D.C.resistivity and chargeability cause the positive response(PR)to increase significantly and decay more ra-pidly.Meanwhile,the NR is advanced and enlarged significantly and decays slower compared with the PR.The influence of time constant is not monotony and there exists an optimal value for producing the maxi-mum NR.As the frequency parameter increases,the PR is caused to decay more rapidly without magni-tude change and the NR is advanced and decays more rapidly with significant increase in magnitude.The influence of frequency parameter is more pronounced than that of time constant. | Yixing Ma Junhua Hu Yanjun Chang Zujian Liu | 2021 | Journal of Earth Science2021，32，1： | 3 |
| 6 | EFFECT OF Z-PINS’ DIAMETER,SPACING AND OVERLAP LENGTH ON CONNECTING PERFORMANCE OF CMC SINGLE LAP JOINT显示文摘The effect of through-thickness reinforcement by composite pins (Z-pins) on the static tensile strength and failure mechanisms of the joints made from ceramic matrix composite (CMC) is investigated. Overlap length of the single lap joint is 15 mm, 20 mm, 23 mm, 37 mm, and 60 mm, respectively. The experimental results indicate that the final failure modes of the joints can be divided into two groups, (a) the bond-line stops debonding until crack encounters Z-pins; and then the adherends break at the location of Z-pins, when overlap length is more than 20 mm; (b) the bond-line detaches entirely and Z-pins are drawn from adherends, when overlap length is equal to 15 mm. A simple effcient computational approach is presented for analyzing the benefit of through-thickness pins for restricting failure in the single lap joints. Here, the mechanics problem is simplified by representing the effect of the pins by tractions acting on the fracture surfaces of the cracked bond-line. The tractions are prescribed as functions of the crack displacement, which are available in simple forms that summarize the complex deformations to a reasonable accuracy. The resulting model can be used to track the evolution of complete failure mechanisms, for example, bond-line initial delamination and ultimate failure associated with Z-pin pullout, ultimate failure of the adherends. The paper simulates connecting performance of the single lap joints with different Z-pins’ diameter, spacing and overlap length; the numerical results agree with the experimental results; the numerical results indicate enlarging diameter and decreasing spacing of Z-pins are in favor of improving the connecting performance of the joints. By numerical analysis method, the critical overlap length that lies between two final failure modes is between 18 mm and 19 mm, when Z-pins’ diameter and spacing are 0.4 mm, 5 mm, respectively. | Yongqiang Tao Guiqiong Jiao Bo Wang Yanjun Chang | 2008 | Acta Mechanica Solida Sinica2008，21，5： | 3 |
| 7 | APPLICATION AND THEORETICAL ANALYSIS OF C/SiC COMPOSITES BASED ON CONTINUUM DAMAGE MECHANICS显示文摘Based on the thermodynamic theory,an orthotropic damage constitutive model was developed to describe the nonlinear mechanical behavior of C/SiC composites.The diferent nonlinear kinematic and isotropic hardening functions were adopted to describe accurately the damage evolution processes.The damage variables were defined with the damaged modulus and the initial undamaged modulus on energy equivalence principle.The initial orthotropy and damage coupling were presented in the damage yield function.Tensile and in-plane shear loading and unloading tests were performed,and a good agreement between the model and the experimental results was achieved. | Yanjun Chang Guiqiong Jiao Keshi Zhang Bo Wang Jiannwen Ju | 2013 | Acta Mechanica Solida Sinica2013，26，5： | 3 |
| 8 | Premium Connection Downhole Tubing Corrosion显示文摘 | Shuanlu Lu Jianmin Xiang Yanjun Kang Zeliang Chang Xunchang Dong Tongguang Zhai | 2008 | Materials Performance2008，，5： | 2 |
| 9 | Lignocellulosic biomass gasification technology in China显示文摘 | Kai Zhang Jian Chang Yanjun Guan Honggang Chen Yongping Yang Jianchun Jiang | 2013 | Renewable Energy2013，，： | 1 |
| 10 | Fracture Analysis of Cast Iron Materials with Cracks Based on Elastoplastic Extended Finite Element Method显示文摘Based on the ABAQUS platform for finite element analysis, the extended finite element method (XFEM) considering elastoplastic constitutive relationship is developed, by which the displacement discontinuity across the crack surface and the strong nonlinearity near the crack tip can be described more accurately. The strip specimens with unilateral cracks and central cracks under uniaxial tension are simulated using the XFEM and the FEM, respectively. The J-integral across the crack on each incremen t is calcula ted using the equivale nt domain integral met hod (EDIM), the interaction integral met hod and the FEM, respectively. The effec ts of mesh size and mesh shape near the crack tip, element type and different calculation methods on the accuracy of J-integral are analyzed. The simulation results show that the XFEM is more accurate than the FEM with the same element size and type. The fracture tests of cast iron specimens with unilateral cracks under uniaxial tension are performed, and the J-integral criterion is valid to predict the fracture initiation in numerical simulation. The critical value of J-integral is calculated using the EDIM of the XFEM. The comparisons demonstrate that the simulated elastoplastic load-displacement curves with the XFEM are in good agreement with the experimental results. | Yanjun Chang Qiao Song Zheng Kuang Keshi Zhang Zhanguang Zheng | 2019 | Acta Mechanica Solida Sinica2019，32，2： | 1 |
| 11 | Lignocellulosic biomass gasification technology in China显示文摘 | ZHANG Kai CHANG Jian GUAN Yanjun | | 0，，： | 1 |
| 12 | Premium Connection Downhole Tubing Corrosion显示文摘 | Shuanlu Lu Jianmin Xiang Yanjun Kang Zeliang Chang Xunchang Dong Tongguang Zhai | 2008 | Materials Performance2008，，5： | 1 |
| 13 | Vitreous Humor:A Review of Biochemical Constituents in Postmortem Interval Estimation显示文摘Postmortem changes in the biochemical constituents of the vitreous humor have been widely used to estimate the postmortem interval(PMI)over the past several decades.However,few reviews have summarized the relationship between the postmortem vitreous biochemical constituents and time of death.Herein,the relationship between PMI and single biochemical components,including vitreous potassium,hypoxanthine,and amino acids,as well as comparisons of each statistical parameter in the formula,is summarized.We also discuss other compounds such as urea and uric acid,which have no direct relationship with PMI.Utility of multiple constituent simultaneous analysis for estimating PMI is being increasingly investigated.The promising idea of using simultaneous analysis of multiple constituents to determine PMI is proposed as a future research direction. | Weichen Li Yunfeng Chang Zijia Cheng Jiang Ling Leiming Han Xingmei Li Yanjun Ding | 2018 | Journal of Forensic Science and Medicine2018，4，2： | 0 |
| 14 | Facile fabrication of ultrathin freestanding nanoporous Cu and Cu-Ag films with high SERS sensitivity by dealloying Mg-Cu(Ag)-Gd metallic glasses显示文摘Nanoporous metals prepared by dealloying have attracted increasing attention due to their interesting size-dependent physical,chemical,and biological properties.However,facile fabrication of metallic ultrathin freestanding nanoporous films(UF-NPFs)by dealloying is still challenging.Herein,we report a novel strategy of facile preparation of flexible Cu,Cu_(3)Ag,and CuAg UF-NPFs by dealloying thick Mg-Cu(Ag)-Gd metallic glass ribbons.During dealloying,the local reaction latent heat-induced glass transition of the precursor ribbons leads to the formation of a solid/liquid interface between the initially dealloyed nanoporous layer and the underlying supercooled liquid layer.Due to the bulging effect of in situ generated H2 on the solid/liquid interface,Cu,Cu_(3)Ag,and CuAg UF-NPFs with thicknesses of~200 nm can self-peel off from the outer surface of the dealloying ribbons.Moreover,it was found that the surfaceenhanced Raman scattering(SERS)detection limit of Rhodamine 6G(R6G)on the Cu and CuAg UF-NPF substrates are 10^(-6)M and 10^(-11)M,respectively,which are lower than most of the Cu and Cu-Ag substrates prepared by other methods.This work presents a reliable simple strategy to synthesize a variety of cost effective and flexible metallic UF-NPFs for functional applications. | Yuan-Yun Zhao Feng Qian Chengliang Zhao Chunxiao Xie Jianguo Wang Chuntao Chang Yanjun Li Lai-Chang Zhang | 2021 | Journal of Materials Science & Technology2021，，11： | 0 |
| 15 | Facile synthesis of metal and alloy nanoparticles by ultrasound-assisted dealloying of metallic glasses显示文摘Metal and alloy nanoparticles synthesized by chemical reduction have attracted increasing attention due to their superior physical,chemical,and biological properties.However,most chemical synthesis processes rely on the use of harsh reducing agents and complicated chemical ingredients.Herein,we report a novel reduction-agent-free and surfactant(stabilizer)-free strategy to synthesize Cu,Ag,Au,Cu-Pt,Cu-Au,Cu-Au-Pt-Pd,and Au-Pt-Pd-Cu nanoparticles by ultrasound-assisted dealloying of Mgbased metallic glasses.The formation mechanism of the metal and alloy nanoparticles is revealed by a detailed investigation of sequential intermediate products.We demonstrate that the glass-liquid phase transition of the initially dealloying metallic glasses,together with the synergistic effect of dealloying and ultrasound-driven ligament-breakage of small enough nanoporous intermediates,play key roles in preparing the uniformly dispersed metal and alloy nanoparticles.This approach greatly simplifies the up-scaling synthesis of monometallic and bimetallic nanoparticles,and also provides a general strategy for synthesizing unprecedented multimetallic nanoparticles. | Yuan-Yun Zhao Feng Qian Wenfeng Shen Chengliang Zhao Jianguo Wang Chunxiao Xie Fengling Zhou Chuntao Chang Yanjun Li | 2021 | Journal of Materials Science & Technology2021，，23： | 0 |
| 16 | Estimating the risk of completion total thyroidectomy using real-world data to guide initial surgical decision-making for patients with clinical low-risk papillary thyroid carcinoma显示文摘Background:Continuing controversy exists in diferent guidelines’recommendations regarding whether total thyroidectomy(TT)or lobectomy is the optimal surgery for patients with low-risk papillary thyroid carcinoma(PTC).Diverse perceptions of the risk of completion TT after lobectomy are the main debate between guidelines and institutions.Methods:Patients who underwent thyroidectomy and prophylactic central lymph node dissection for≤4 cm PTC(January 2007 to December 2020)by high-volume surgeons were included.Patients with preoperatively known highrisk characteristics or suspicious bilateral multifocality were excluded.The pathological fndings were defned as the risk stratifcations of completion TT from low to high to evaluate which initial surgical procedure could allow more patients to meet the criteria of optimal surgical extent.Results:Of 4965 consecutive patients met lobectomy criteria as the initial operation.Aggressive histological subtypes were found in 2.5%of patients,T3b disease in 1.1%,T4 disease in 3.1%,LNs involved≤5 in 29.5%,LNs involved>5 in 3.1%,and incidental bilateral multifocality in 7.9%.According to our defned risk stratifcation system,TT and lobectomy would be considered the optimal initial procedure in 12.0%and 67.2%PTC patients with a tumor≤1 cm and 28.7%and 36.6%in the 1-4 cm groups in our real-world cohort,respectively.Conclusion:Lobectomy alone,as an initial procedure,could allow more low-risk PTC patients with a tumor either≤1 cm or 1-4 cm to achieve the optimal surgical extent.Moreover,surgeons should balance the high-risk characteristics and complication risks during surgery to re-evaluate surgical decision-making. | Wen Liu Xiangxiang Zhan Zhizhong Dong Yanjun Su Jianming Zhang Jun Qian Yunhai Ma Chang Diao Ruochuan Cheng | 2022 | Holistic Integrative Oncology2022，1，1： | 0 |
| 17 | Computational investigation of contraction behavior in a liquid-solid fluidized bed显示文摘Contraction behavior of a liquid-solid fluidized bed has been investigated numerically. Based on a simple hydrodynamic model proposed by Brandani and Zhang (2006), a case study for solid particles with a density of 3,000 kg/m3 and a diameter of 2.5× 10 -3 m is simulated in a two-dimensional fluidized bed (0.50 m height and 0.10 m width). Due to the continuity of numerical computation, there is a transition region between two zones of different solid holdups when the liquid velocity is suddenly changed. The top, middle and bottom interfaces are explored to obtain a reasonable interface height. The simulated results show that the steady time of the middle interface is more close to Gibilaro's theory and suitable for describing the contraction process of a phase interface. Furthermore, the effect of liquid velocity and particle diameter is simulated in the other two-dimensional fluidized bed (0.10 m height and 0.02 m width) where the solid particles are glass beads whose properties are similar to those of the catalyst particles used in the alkylation process.The results also show good agreement with Gibilaro's theory, and that larger particles lead to a more obvious bed contraction. | Yao Xiuying Guan Yanjun Chang Jian Zhang Kai Jiang Jianchun | 2012 | Petroleum Science2012，9，1： | 0 |
| 18 | 3D Multilayered Turtle Shell Models for Image Steganography显示文摘By embedding secret data into cover images,image steganography can produce non-discriminable stego-images.The turtle shell model for data hiding is an excellent method that uses a reference matrix to make a good balance between image quality and embedding capacity.However,increasing the embedding capacity by extending the area of basic structures of the turtle shell model usually leads to severe degradation of image quality.In this research,we innovatively extend the basic structure of the turtle shell model into a three-dimensional(3D)space.Some intrinsic properties of the original turtle shell model are well preserved in the 3D version.Theoretic analysis shows that the new proposed models have good performance both in the image quality and in the complexity of the reference matrix.Our experimental results justify the theoretic conclusions. | Ji-Hwei Horng Juan Lin Yanjun Liu Chin-Chen Chang | 2020 | Computer Modeling in Engineering & Sciences2020，，11： | 0 |
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