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| 1 | Estimation of Undrained Bearing Capacity for Offshore Soft Foundations with Cyclic Load显示文摘The degradation strength of soils under cyclic loading is studied and a method for deter-mining the cyclic degradation strength with cyclic triaxial tests is given in the paper.Furthermore,a dum-my static method for estimating the undrained bearing capacity for offshore soft foundation under waveloads is developed.It can consider the effect of the difference of cyclic stress for different parts of the foun-dation on both the degradation strength of the foundation soil and the bearing capacity so that the esti-mated result can better reflect the real condition of foundation under cyclic loading.The method can be ap-plied to plane and space problem. | Wang, JH Liu, YF Xing, Y Di, HM | 1998 | China Ocean Engineering1998，13，2： | 18 |
| 2 | Contribution of ghrelin to functional gastrointestinal disorders' pathogenesis显示文摘Functional gastrointestinal disorders(FGID) are heterogeneous disorders with a variety of clinical manifestations, primarily defined by signs and symptoms rather than a definite underlying cause. Their pathophysiology remains obscure and, although it is expected to differ according to the specific FGID, disruptions in the brain-gut axis are now thought to be a common denominator in their pathogenesis. The hormone ghrelin is an important component of this axis,exerting a wide repertoire of physiological actions, including regulation of gastrointestinal motility and protection of mucosal tissue. Ghrelin's gene shows genetic polymorphism, while its protein product undergoes complex regulation and metabolism in the human body. Numerous studies have studied ghrelin's relation to the emergence of FGIDs, its potential value as an index of disease severity and as a predictive marker for symptom relief during attempted treatment. Despite the mixed results currently available in scientific literature, the plethora of statistically significant findings shows that disruptions in ghrelin genetics and expression are plausibly related to FGID pathogenesis. The aim of this paper is to review current literature studying these associations, in an effort to uncover certain patterns of alterations in both genetics and expression, which could delineate its true contribution to FGID emergence, either as a causative agent or as a pathogenetic intermediate. | Tilemachos Koutouratsas Theodora Kalli Georgios Karamanolis Maria Gazouli | 2019 | World Journal of Gastroenterology2019，25，5： | 14 |
| 3 | Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession显示文摘Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include instantaneous exposed punctuated surface, drowned punctuated surface as well as their relative surface. The development of instantaneous punctuated surface used as the boundary of meter-scale cyclic sequence brings about the limitations of Walter’s Law on the explanation of facies distribution in time and space, and reaffirm the importance of Sander’s Rule on analysis of stratigraphic records. These non-continuous surface could be traced for long distance and some could be correlative within same basin range. The study of meter-scale cyclic sequences and their regularly vertical stacking patterns in long-term sequences indicate that the research into cyclicity of stratigraphic records is a useful way to get more regularity from stratigraphic records that are frequently complex as well as non-integrated. | Mei Mingxiang Xu Debin Zhou Hongrui Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 | 2000 | Journal of Earth Science2000，19，4： | 12 |
| 4 | Mechanical properties and failure modes of stratified backfill under triaxial cyclic loading and unloading显示文摘Multiple filling of gobs will lead to a layered structure of the backfill.To explore the influence of layering structure on the mechanical properties and failure modes of backfill,different backfill specimens were prepared with a cement/sand ratio of 1:4,a slurry concentration of 75%,and backfilling times of 1,2,3 and 4,separately.Triaxial cyclic loading and unloading experiments were carried out.The results show that with an increase in backfilling time,the peak strength of backfill decreases as a polynomial function and the peak strain increases as an exponential function.The cyclic load enhances the linear characteristic of backfill deformation.The loading and unloading deformation moduli have a linear negative correlation with the backfilling time.The unloading deformation modulus is always slightly higher than the loading deformation modulus.The failure modes of stratified backfill are mainly characterized by conjugate shear failure at the upper layer and tensile failure across the layer plane,and there is usually no damage in the lower layer away from the loading area. | Wang Jie Song Weidong Cao Shuai Tan Yuye | 2019 | International Journal of Mining Science and Technology2019，29，5： | 11 |
| 5 | Strength degradation of sandstone and granodiorite under uniaxial cyclic loading显示文摘Change in mechanical properties of rocks under static loading has been widely studied and documented.However, the response of rocks to cyclic loads is still a much-debated topic. Fatigue is the phenomenon when rocks under cyclic loading fail at much lower strength as compared to those subjected to the monotonic loading conditions. A few selected cored granodiorite and sandstone specimens have been subjected to uniaxial cyclic compression tests to obtain the unconfined fatigue strength and life. This study seeks to examine the effects of cyclic loading conditions, loading amplitude and applied stress level on the fatigue life of sandstone, as a soft rock, and granodiorite, as a hard rock, under uniaxial compression test. One aim of this study is to determine which of the loading conditions has a stronger effect on rock fatigue response. The fatigue response of hard rocks and soft rocks is also compared. It is shown that the loading amplitude is the most important factor affecting the cyclic response of the tested rocks. The more the loading amplitude, the shorter the fatigue life, and the greater the strength degradation. The granodiorite specimens showed more strength degradation compared to the sandstone specimens when subjected to cyclic loading. It is shown that failure modes of specimens under cyclic loadings are different from those under static loadings. More local cracks were observed under cyclic loadings especially for granodiorite rock specimens. | Rashid Geranmayeh Vaneghi Behnam Ferdosi Achola D.Okoth Barnabas Kuek | 2018 | Journal of Rock Mechanics and Geotechnical Engineering2018，10，1： | 11 |
| 6 | Effect of rock joint roughness on its cyclic shear behavior显示文摘Rock joints are often subjected to dynamic loads induced by earthquake and blasting during mining and rock cutting. Hence, cyclic shear load can be induced along the joints and it is important to evaluate the shear behavior of rock joint under this condition. In the present study, synthetic rock joints were prepared with plaster of Paris(Po P). Regular joints were simulated by keeping regular asperity with asperity angles of 15°-15° and 30°-30°, and irregular rock joints which are closer to natural joints were replicated by keeping the asperity angles of 15°-30° and 15°-45°. The sample size and amplitude of roughness were kept the same for both regular and irregular joints which were 298 mm×298 mm×125 mm and 5 mm, respectively. Shear test was performed on these joints using a large-scale direct shear testing machine by keeping the frequency and amplitude of shear load under constant cyclic condition with different normal stress values. As expected, the shear strength of rock joints increased with the increases in the asperity angle and normal load during the first cycle of shearing or static load. With the increase of the number of shear cycles, the shear strength decreased for all the asperity angles but the rate of reduction was more in case of high asperity angles. Test results indicated that shear strength of irregular joints was higher than that of regular joints at different cycles of shearing at low normal stress. Shearing and degradation of joint asperities on regular joints were the same between loading and unloading, but different for irregular joints. Shear strength and joint degradation were more significant on the slope of asperity with higher angles on the irregular joint until two angles of asperities became equal during the cycle of shearing and it started behaving like regular joints for subsequent cycles. | S.M.Mahdi Niktabar K.Seshagiri Rao Amit Kumar Shrivastava | 2017 | Journal of Rock Mechanics and Geotechnical Engineering2017，9，6： | 10 |
| 7 | Construction of Type-II QC LDPC Codes Based on Perfect Cyclic Difference Set显示文摘Quasi-cyclic(QC) Low-density paritycheck(LDPC) codes are constructed from combination of weight-0(null matrix) and Weight-2(W2) Circulant matrix(CM), which can be seen as a special case of the general type-II QC LDPC codes. The shift matrix of the codes is built on the basis of one integer sequence, called perfect Cyclic difference set(CDS), which guarantees the girth of the code at least six. Simulation results show that the codes can perform well in comparison with a variety of other LDPC codes. They have excellent error floor and decoding convergence characteristics. | ZHANG Lijun LI Bing CHENG Leelung | 2015 | Chinese Journal of Electronics2015，24，1： | 10 |
| 8 | The Mechanism Analysis of Seafloor Silt Liquefaction Under Wave Loading显示文摘The sediment in Chengbei area of the Huanghe (Yellow River) subaqueous delta is the object of a reseach project in this article. The accumulating and dissipating effects following the change of time are considered first in the study area and the distributing curves of excess pore water pressure along with time and depth in the soil stratum are gained; the possibility of silt liquefaction is evaluated using the computing values and the affecting depth of liquefaction is given. This paper quantitatively analyzes the dynamic response of seafloor soil under the cyclic loading of waves and makes an inquiry into the instable mechanism of soil. | Yang Shaoli , Shen Weiquan Yang Zuosheng \Assistant, The Institute of Estuarine and Coastal Studies, Ocean University of Qingdao, Qingdao 266003 . Professor, The Institute of Estuarine and Coastal Studies, Ocean University of Qingdao, Qingdao 266003 | 1995 | China Ocean Engineering1995，10，4： | 8 |
| 9 | The role of chloroplast NAD(P)H dehydrogenase in protection of tobacco plant against heat stress显示文摘After incubation at 42℃ for more than 48 h, brown damages occurred on the stems of tobacco (Nicotiana tabacum L.) ndhC-ndhK-ndhJ deletion mutant (?ndhCKJ), followed by wilt of the leaves, while less the phenotype was found in its wild type (WT). Analysis of the kinetics of post-illumination rise in chlorophyll fluorescence indicated that the PSI cyclic electron flow and the chlororespiration mediated by NAD(P)H dehydrogenase (NDH) was significantly enhanced in WT under the high temperature. After leaf disks were treated with methyl viologen (MV), photosynthetic apparatus of ?ndhCKJ exhibited more severe photo-oxidative damage, even bleaching of chlorophyll. Analysis of P700 oxidation and reduction showed that the NDH mediated cyclic electron flow probably functioned as an electron competitor with Mehler reaction, to reduce the accumulation of reactive oxygen species (ROS). When leaf disks were heat stressed at 42℃ for 6 h, the photochemical activity declined more markedly in ?ndhCKJ than in WT, accompanied with more evident decrease in the amount of soluble Rubisco activase. In addition, the slow phase of millisecond-delayed light emission (ms-DLE) of chlorophyll fluorescence indicated that NDH was involved in the building-up of transthy-lakoid proton gradient (?pH), while the consumption of ?pH was highly inhibited in ?ndhCKJ after heat stress. Based on the results, we supposed that the cyclic electron flow mediated by NDH could be stimulated under the heat stressed conditions, to divert excess electrons via chlororespiration pathway, and sustain CO2 assimilation by providing extra ?pH, thus reducing the photooxidative damage. | WANG Peng YE Jiyu SHEN Yungang MI Hualing | 2006 | Science China(Life Sciences)2006，49，4： | 8 |
| 10 | Electrochemical performance of carbon nanotube-modified LiFePO_4 cathodes for Li-ion batteries显示文摘Carbon nanotubes (CNTs) and acetylene black (AB) were dispersed synchronously or separately between LiFePO4 (LFP) particles as conducting agents during the course of manufacture of LiFePO4 cathodes. The morphology and electrochemical performances of as-prepared LiFePO4 were evaluated by means of transmission electron microscopy (TEM), charge-discharge test, electrochemical impedance spectroscope (EIS) and cyclic voltammetry (CV). CNTs contribute to the interconnection of the isolated LiFePO4 or carbon particles. For the CNTs-modified LiFePO4, it exhibits excellent performance in terms of both specific capacity and cycle life. The initial discharge capacity is 147.9 mA·h/g at 0.2C rate and 134.2 mA·h/g at 1C rate, keeping a capacity retention ratio of 97% after 50 cycles. The results from EIS indicate that the impedance value of the solid electrolyte interface decreases. The cyclic voltammetric peak profiles is more symmetric and spiculate and there are fewer peaks. CNTs are promising conductive additives candidate for high-power Li-ion batteries. | 陈召勇 朱华丽 朱伟 张建利 李奇峰 | 2010 | Transactions of Nonferrous Metals Society of China2010，20，4： | 8 |
| 11 | A Calcium-Dependent Protein Kinase Interactswith and Activates A Calcium Channel toRequlate Pollen Tube Growth显示文摘ABSTRACT Calcium, as a ubiquitous second messenger, plays essential roles in tip-growing cells, such as animal neu-rons, plant pollen tubes, and root hairs. However, little is known concerning the regulatory mechanisms that code anddecode Ca2+ signals in plants. The evidence presented here indicates that a calcium-dependent protein kinase, CPK32,controls polar growth of pollen tubes. Overexpression of CPK32 disrupted the polar growth along with excessive Ca2+accumulation in the tip. A search of downstream effector molecules for CPK32 led to identification of a cyclic nucleotide-gated channel, CNGC18, as an interacting partner for CPK32. Co-expression of CPK32 and CNGC18 resulted in activationof CNGC18 in Xenopus oocytes where expression of CNGC18 alone did not exhibit significant calcium channel activity.Overexpression of CNGC18 produced a growth arrest phenotype coupled with accumulation of calcium in the tip, simi-lar to that induced by CPK32 overexpression. Co-expression of CPK32 and CNGC18 had a synergistic effect leading tomore severe depolarization of pollen tube growth. These results provide a potential feed-forward mechanism in whichcalcium-activated CPK32 activates CNGC18, further promoting calcium entry during the elevation phase of Ca2+ oscilla-tions in the polar growth of pollen tubes. | | 2014 | Molecular Plant2014，7，2： | 7 |
| 12 | Emerging CoMn-LDH@MnO2 electrode materials assembled using nanosheets for flexible and foldable energy storage devices显示文摘CoMn layered double hydroxides(CoMn-LDH)are promising electrode materials for supercapacitors because of their excellent cyclic stability.However,they possess relatively low capacitances.In this work,hybrid CoMn-LDH@MnO2 products grown on Ni foams were obtained through a facile hydrothermal method.The as-synthesized samples employed as electrodes deliver a specific capacitance of 2325.01 F g^-1 at 1 A g^-1.An assembled asymmetric supercapacitor using these products as positive electrodes shows a maximum energy density of 59.73 W h kg^-1 at 1000.09 W kg^-1.The prominent electrochemical performance of the as-prepared electrodes could be attributes to hierarchical structures.These findings suggest that hybrid structures might be potential alternatives for future flexible energy storage devices. | Yue Zhao Jiafeng He Meizhen Dai Depeng Zhao Xiang Wu Baodan Liu | 2020 | Journal of Energy Chemistry2020，29，6： | 7 |
| 13 | INTERFACIAL DEBONDING OF COATED-FIBER-REINFORCED COMPOSITES UNDER TENSION-TENSION CYCLIC LOADING显示文摘A new degradation function of the friction coefficient is used.Basedon the double shear-lag model and Paris formula,the interracial damage of coated-fiber-reinforced composites under tension-tension cyclic loading is studied.The effectsof strength and thickness of the coating materials on the debond stress,debond rateas well as debond length are simulated. | 石志飞 周利民 | 2000 | Acta Mechanica Sinica2000，16，4： | 7 |
| 14 | DNA Immobilization on Nano-Gold Modified Glassy Carbon Electrode显示文摘CT-DNA were electrochemically immobilized on the surfaces of both nano-goldmodified glassy carbon electrode and bare glassy carbon electrode. The cyclic voltammetricbehavior of Co (phen)33+adsorbed on the immobilized DNA was studied. Increase in the peakcurrent of Co (phen)33+ redox reaction was obtained on nano-gold modified glassy carbon electrode.The result suggests that more DNA molecules were immobilized on this electrode and nano-goldmodification can enhance the heterogeneous electron transfer rate constant of the Co (phen)33+. | Xiang Qin LIN Qian MIAO Bao Kang JIN(Department of Chemistry. University of Science and Technology of China, Hefei 230026)(Department of Chemistry. AnHui University. Hefei 230039) | 1999 | Chinese Chemical Letters1999，10，2： | 7 |
| 15 | Two New Cyclic Peptides from Psammosilene tunicoides显示文摘From Psammosilene tunicoides W. C. Wu et C. Y Wu, two cyclic octapeptides (namedpsammosilenins A and B) were isolated. Their structures were determined as cyclo(-Pro1-phe1-Pro2-Phe2-Phe3-Ala-Pro3-Leu-) and cyclo(-Pro1-Gly-Phe1-Val-Pro2-Phe2-Thr-Ile) by spectroscopicmethods. | Zhong Tao DING You Chu WANG Jun ZHOU Ning Hua TAN Hou Ming WU(1Laboratory of Phytochemisty, Kunming institute of Botany, Academia Sinica, Kunming 650204)(2Department of Chemistry, Yunnan University, Kunming 650091)(3State Key Laboratory of Bio-Organic | 1999 | Chinese Chemical Letters1999，10，12： | 6 |
| 16 | Preparation of reduced sensitivity co-crystals of cyclic nitramines using spray flash evaporation显示文摘The present day weapon technology demands novel energetic materials that exhibit simultaneous high explosive yield and reduced sensitivity.This article demonstrates application of spray evaporation to prepare reduced sensitive co-crystals of high performance nitramine explosives like HMX and CL-20 with a relatively less insensitive explosive 1,1-diamino-2,2-dinitroethylene or FOX-7.Stronger intermolecurar hydrogen bonding in FOX-7 is responsible for limited solubility in nost of o rganic solvents.Large solubility differences of FOX-7 with HMX and CL-20 restricts ifs co-crystallization through classical methods that yields thermodynamically favorable product.Spray flash evaporation,a kinetic crystallization method,has been therefore adopted and could successfully produce CL-20/FOX-7(2:1) and HMX/FQX-7(4:1) co-crystals.The fine powdered materials obtained were characterized by SEM,powder XRD,Raman spectro scopy,DSC-TGA etc.Multipoint Raman spectra showed consistent occurrence of spectral features indicating stoichiometric co-existence of ingredients in the crystal lattices.DSC analysis showed absence of all thermally assisted solidsolid phase transformation in the co-crystals as they were observed in pristine materials.The thermal stability calculated in terms of activation barrier fordecomposition,revealed the CL-20/FOX-7 co-crystal to be interlediately stable on comparison to their constituents while,the HMX/FOX-7 co-crystal is more stable.Compared to pure HMX and CL-20,both the co-crystals have shown higher insensitivity to impact force,suggesting them to be suitable for future generation insensitive munitions. | Mrinal Ghosh AKSikder Shaibal Banerjee MBTalawar NSikder | 2020 | Defence Technology(防务技术)2020，16，1： | 6 |
| 17 | A Stepwise Annulation for the Transformation of Cyclic Ketones to Fused 6 and 7-Membered Cyclic Enimines and Enones显示文摘The efficient construction of functionalized polycyclic structures is an imports nt objective in organic synthesis.Herein,we disclose a three-step'[2+n]'annulation method for the transformation of cyclic ketones to fused enimines and enones.The method relies on the Suzuki coupling reaction and the amide reductive alkenylation reaction.A series of fused bicyclic(6/6,6/7,8/7)and tricyclic(6/6/6;6/6/7,6/5/7)ring systems bearing an α,β-enimine or an α,β-enone functionality have been synthetized in good overall yields. | Dong-Ping Wu Qian He Dong-Huang Chen Jian-Liang Ye Pei-Qiang Huang | 2019 | Chinese Journal of Chemistry2019，37，4： | 6 |
| 18 | A macroscopic multi-mechanism based constitutive model for the thermo-mechanical cyclic degeneration of shape memory effect of NiTi shape memory alloy显示文摘A macroscopic based multi-mechanism constitutive model is constructed in the framework of irreversible thermodynamics to describe the degeneration of shape memory effect occurring in the thermo-mechanical cyclic deformation of NiTi shape memory alloys(SMAs). Three phases,austenite A, twinned martensite Mtand detwinned martensite M^d, as well as the phase transitions occurring between each pair of phases( A → M^t, M^t→ A, A → M^d,M^d→ A, and M^t→ M^d) are considered in the proposed model. Meanwhile, two kinds of inelastic deformation mechanisms, martensite transformation-induced plasticity and reorientation-induced plasticity, are used to explain the degeneration of shape memory effects of NiTi SMAs. The evolution equations of internal variables are proposed by attributing the degeneration of shape memory effect to the interaction between the three phases(A, M^t, and M^d) and plastic deformation. Finally, the capability of the proposed model is verified by comparing the predictions with the experimental results of NiTi SMAs. It is shown that the degeneration of shape memory effect and its dependence on the loading level can be reasonably described by the proposed model. | Chao Yu Guozheng Kang Qianhua Kan | 2017 | Acta Mechanica Sinica2017，33，3： | 6 |
| 19 | A class of binary cyclic codes with five weights显示文摘In this paper, the dual code of the binary cyclic code of length 2 n-1 with three zeros α, α t 1 and α t 2 is proven to have five nonzero Hamming weights in the case that n 4 is even and t1 = 2 n/2 + 1, t2 = 2 n-1-2 n/2+1 + 1 or 2 n/2 + 3, where α is a primitive element of the finite field F 2 n . The dual code is a divisible code of level n/2+1, and its weight distribution is also completely determined. When n = 4, the dual code satisfies Ward's bound. | LI ChunLei 1 , ZENG XiangYong 1, & HU Lei 2 1 Faculty of Mathematics and Computer Science, Hubei University, Wuhan 430062, China 2 The State Key Laboratory of Information Security, Graduate School of Chinese Academy of Sciences, Beijing 100049, China | 2010 | Science China Mathematics2010，53，12： | 5 |
| 20 | Effect of electroacupuncture on arginine vasopressin-induced endolymphatic hydrops显示文摘OBJECTIVE: To investigate the influence of electroacupuncture(EA) on experimentally induced endolymphatic hydrops(EH) in guinea pigs, and elucidate the association between the dehydrating effect of EA and changes in stria vascularis ultrastructure and expression of vasopressin type 2 receptor(V2R), cyclic adenosine monophosphate(cAMP),and aquaporin 2(AQP2) in the endolymphatic sac(ES).METHODS: The EH model was established by intraperitoneal injection of arginine vasopressin(AVP).As a treatment, EA was delivered to Baihui(GV 20)and Tinggong(SI 19) acupoints, once daily for 10 consecutive days. For histomorphological studies,degree of cochlear hydrops was evaluated by hematoxylin-eosin staining, and the ratio of scala media(SM) area to SM + scala vestibuli area was calculated. In mechanical studies, ultrastructural changes in stria vascularis tissue were examined by transmission electron microscopy. In addition, cAMP levels and mRNA expression levels of V2 R and AQP2 in the ES were compared among groups.RESULTS: EA treatment significantly reduced cochlear hydrops compared with hydropic guinea pigs(P = 0.015). Furthermore, EA attenuated ultrastructural changes in the stria vascularis tissue following EH, significantly upregulated the expression of V2 R(P = 0.016), and attenuated AVP-induced upregulation of both cAMP(P = 0.038) and AQP2 expression(P = 0.017) in the ES.CONCLUSION: Collectively, the results of the present study suggest that the dehydrating effect of EA is associated with improvement of stria vascularis ultrastructure and V2 R-cAMP-AQP2 signaling pathway regulation in the ES. | Jiang Liyuan He Jiaojun Chen Xixi Chen Huade | 2019 | Journal of Traditional Chinese Medicine2019，39，2： | 5 |
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