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Extension/compression-controlled complete Band Gaps in 2D chiral Square-Lattice-Like Structures

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Acta Mechanica Solida Sinica 2018年第1期31卷 51-65页

作者： Y. L. Huang N. Gao w.Q. chen R.H. Bao Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China State Key Lab of cAD & cG Zhejiang University Hangzhou 310058 China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University Hangzhou 310027 China Soft Matter Research center Zhejiang University Hangzhou 310027 China

Achieving tunable band gaps in a structure by external stimuli is of great importance in acoustic applications. This paper aims to investigate the tunability of band gaps in square-lattice-like elastic periodic structures that are usually not featured with notable band gaps. Endowed with chirality, the periodic structures here are able to undergo imperfection-insensitive large deformation under extension or compression. The influences of geometric parameters on band gaps are discussed via the nonlinear finite element method. It is shown that the band gaps in such structures with curved beams can be very rich and, more importantly, can be efficiently and robustly tuned by applying appropriate mechanical loadings without inducing buckling. As expected, geometry plays a more significant role than material nonlinearity does in the evolution of band gaps. The dynamic tunability of band gaps through mechanical loading is further studied. Results show that closing, opening, and shifting of band gaps can be realized by exerting real-time global extension or compression on the structure. The proposed periodic structure with well-designed chiral symmetry can be useful in the design of particular acoustic devices.

关键词： Band gap Tunability Square-lattice-like periodic structure chiral symmetry,Large deformation

Temporal and Spatial Distribution of Elements in a Small catchment, and Buffer Function of wetland in Longgan Lake, china

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chinese Journal Of Geochemistry 2004年第1期23卷 37-45页

作者：吴艳宏王苏民 R.w.Barttarbee 朱育新 Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China EcRc Department of Geography University College of London 26 Bedford Way London WC1H 0AP U.K.

wetland is the conjunction of lake and terrene where human activities are concentrated. From the viewpoints of material transport and cycling in the terrene-lake system, wetland is the buffer where sand and mud, heavy metals, pollutants and nutrients are tarried. In this paper, we provide a case study based on the temporal and spatial distribution of elements in the wangling River catchment, a small sub-catchment of Longgan Lake in the middle reaches of the Yangtze River. we have found that wetland can buffer major heavy metals such as cr, cu, etc. significantly, but has a little buffer function to some active elements such as Fe and Mn, which are always transported as solutions. Human activities not only influence the distribution of elements, but also weaken the buffer function of wetland. Intensive human activities in the Longgan Lake area in the past 70 years have been recorded in stream, wetland and lake sediments, especially the human activity events such as deforesting and reclaiming on a large scale in 1958 and the 1980’s. Human activities caused the increase of sedimentation rates since the 1950’s, as well as the increase of elements’ concentrations. The extensive use of fertilizers and pesticides since the 1960’s have led to the increase of total P concentrations. Increasing SO-2 emission accelerate the process of cation exchange in soil, and enhance the leaching of Mn out of soils. Permanent storing of water causes the soil gleyification that also intensifies the leaching of Mn. These are two major reasons for the obvious increase of manganese concentrations in recent 20 years in Longgan Lake. Intensive human activities since the 1950s’ have intensified the population in this region and thus destroyed the buffer function of wetland.

关键词：沼泽地河沙淤泥沉积重金属

Biomass torrefaction in a slot-rectangular spouted bed reactor

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Particuology 2019年第1期17卷 154-162页

作者： Ziliang wang c. Jim Lim John R. Grace Department of chemical and Biological Engineering. University of British columbia Vancouver. Canada

Sawdust was subjected to torrefaction in a "semi-batch" slot-rectangular spouted bed (SRSB) reactor at temperatures from 240 to 330℃ and biomass feed rates from 220 to 710g/*** spouting of the sawdust was achieved in the slot-rectangular spouted bed,although the pressure drop across the reactor was observed to *** to the biomass feed rate,the temperature had a greater effect on the biomass weight loss and energy *** in temperature were found to promote weight loss of the sawdust while decreasing the energy *** main solid product was the torrefied sawdust,which remained in the SRSB reactor and was captured by a *** ratio of the torrefied biomass removed by the cyclone to the total torrefied biomass increased along with both the feed rate and *** undergoing torrefaction,6.7%-39.2% of the original sawdust mass was lost while 67.4%-98.7% of its energy was *** torrefied sawdust had a higher carbon content but less oxygen,hydrogen and volatiles,along with a greater higher heating value and increased density compared to the raw *** size of the sawdust particles also decreased markedly during the torrefaction process.

关键词： Torrefaction Slot-rectangular spouted bed reactor Temperature Biomass feed rate Torrefied sawdust property

XRD Synchrotron Study of carbide Precipitation in Martensitic Steels During Tempering

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 553-557页

作者： c.Bellot P.Lamesle D.Delagnes Universit de Toulouse Mines Albi INSAISAE IcA(Institut clment Ader) campus Jarlard Aubert&Duval

In order to improve the knowledge of the precipitation mechanism in martensitic steels containing carbon,XRD synchrotron experiments were performed. Firstly, the influence of Ni,co and Al were studied and it was found that the precipitation of iron carbides occurs in same way as in Fe-c steel. However, with the addition of molybdenum and chromium in same steels, XRD synchrotron investigations clearly showed alloyed carbides directly precipitate, thereby preventing the iron carbides formation.

关键词： carbon Martensite Iron carbide cementite Precipitation mechanism

Nonlinear properties of quantum dot semiconductor optical amplifiers at 1.3μm

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chinese Optics Letters 2008年第10期6卷 724-726页

作者： D. Bimberg c. Meuer M. Lammlin Institut fur Festkorperphysik Technische Universitat Berlin

The dynamics of nonlinear processes in quantum dot （QD） semiconductor optical amplifiers investigated. Using small-signal measurements, the suitabilities of cross-gain and cross-phase as well as four wave mixing （FwM） for wavelength conversion are examined. The cross-gain is found to be suitable for wavelength conversion up to a frequency of 40 GHz. （SOAs） are modulation modulation

关键词： cross phase modulation Four wave mixing Optical networks Quantum dots Semiconductor optical amplifiers wavelength conversion

Is it time to rethink combined liver-kidney transplant in hepatitis c patients with advanced fibrosis?

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world Journal of Hepatology 2017年第5期9卷 288-292页

作者： Niraj James Shah Mark w Russo Department of Medicine Division of Dige-stive Diseases the University of Mississippi Medical Center Transplant center-carolinas Medical center 6th Floor Morehead Medical Plaza

AIM To reduce hepatic and extrahepatic complications of chronic hepatitis c in kidney transplant *** we conducted a systematic review of kidney only transplant in patients with hepatitis c and advanced *** The 5 year patient survival of kidney transplant recipients with and without hepatitis c cirrhosis ranged from 31% to 90% and 85% to 92%, respectively. Hepatitis c kidney transplant recipients had lower 10-year survival when compared to hepatitis B patients, 40% and 90% respectively. There were no studies that included patients with virologic cure prior to kidney transplant that reported post-kidney transplant outcomes. There were no studies of direct acting antiviral therapy and effect on patient or graft survival after kidney transplantation. cONcLUSION Data on kidney transplant only in hepatitis c patients that reported inferior outcomes were prior to the development of potent direct acting antiviral. with the development of potent directing acting antiviral therapy for hepatitis c with high cure rates studies are needed to determine if patients with hepatitis c, including those with advanced fibrosis, can undergo kidney transplant alone with acceptable long term outcomes.

关键词： cirrhosis/cirrhotics Renal transplantation Kidney transplantation Mortality Systematic review Graft outcomes Meta-analysis

Fifty Years of water Sensitive Urban Design, Salisbury, South Australia

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 63-72页

作者： John c. Radcliffe Declan Page Bruce Naumann Peter Dillon cSIRO Land and water Private Bag 2 Glen Osmond South Australia 5064 Australia city of Salisbury 12 James St Salisbury South Australia 5108 Australia

Australia has developed extensive policies and guidelines for the management of its water. The city of Salisbury, located within metropolitan Adelaide, South Australia, developed rapidly through urbanisation from the 1970s. water sensitive urban design principles were adopted to maximise the use of the increased rim-off generated by urbanisation and ameliorate flood risk. Managed aquifer recharge was introduced for storing remediated low-salinity stormwater by aquifer storage and recovery （ASR） in a brackish aquiter for subsequent lrngatlon. Ibis paper outlines now a municipal government has progressively adopted principles of water Sensitive Urban Design during its development within a framework of evolving national water policies. Salisbury＇s success with stormwater harvesting led to the formation of a pioneering w aterbusiness that includes linking projects from nine sites to provide a non-potable supply of 5 ×10^6 m^3 year. These installations hosted a number of applied research projects addressing well configuration, water quality, reliability and economics and facilitated the evaluation of its system as a potential potable water source. The evaluation showed that while untreated stonnwater contained contaminants, subsurface storage and end-use controls were sufficient to make recovered water sale for public open space irrigation, and with chlorination acceptable lbr third pipe supplies. Drinking water quality could be achieved by adding microfiltration, disinfection with UV and chlorination. The costs that would need to be expended to achieve drinking water safety standards were found to be considerably less than the cost of establishing dual pipe distribution systems. The full cost of supply was determined to be AUD$1.57 m ＂ for non-potable water for pubhc open space lrngatlon much cheaper than mares water, AUD $3.45 m at that time. Producing and storing potable water was found to cost AUDS1.96 to $2.24 m .

关键词： Managed Aquifer Recharge (MAR) Stormwater harvesting water recycling drinking water Low impact development water sensitive urban design

An equivalence canonical form of a matrix triplet over an arbitrary division ring with applications

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Science china Mathematics 2011年第5期54卷 907-924页

作者： wANG Qingwen van der wOUDE J. w. YU Shaowen Department of Mathematics Shanghai University Shanghai 200444 China Faculty of Electrical Engineering Mathematics and Computer ScienceDelft University of Technology Mekelweg 4 2628 CD Delft The Netherlands Department of Mathematics East China University of Science and Technology Shanghai 200237 China

we in this paper give a decomposition concerning the general matrix triplet over an arbitrary divisionring F with the same row or column numbers. we also design a practical algorithm for the decomposition of thematrix triplet. As applications, we present necessary and suficient conditions for the existence of the generalsolutions to the system of matrix equations DXA = c1, EXB = c2, F Xc = c3 and the matrix equation AXD + BY E + cZF = Gover F. we give the expressions of the general solutions to the system and the matrix equation when thesolvability conditions are satisfied. Moreover, we present numerical examples to illustrate the results of thispaper. we also mention the other applications of the equivalence canonical form, for instance, for the compressionof color images.

关键词： division ring linear matrix equation equivalence canonical form of a matrix triplet decomposition

The role of endoscopy in the management of hereditary diffuse gastric cancer syndrome

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world Journal of Gastroenterology 2019年第23期25卷 2878-2886页

作者： Shria Kumar Jessica M Long Gregory G Ginsberg Bryson w Katona Division of Gastroenterology University of Pennsylvania Perelman School of MedicinePhiladelphiaPA 19104United States Division of Hematology and Oncology University of Pennsylvania Perelman School of MedicinePhiladelphiaPA 19104United States

Hereditary diffuse gastric cancer(HDGc) syndrome is an inherited cancer risk syndrome associated with path-ogenic germline cDH1 variants. Given the high risk for developing diffuse gastric cancer, cDH1 carriers are recommended to undergo prophylactic total gastrectomy for cancer risk reduction. current guidelines recommend upper endoscopy in cDH1 carriers prior to surgery and then annually for individuals deferring prophylactic total *** of individuals from HDGc families without cDH1 pathogenic variants remains less clear, and management of families with cDH1 pathogenic variants in the absence of a family history of gastric cancer is particularly problematic at present. Despite adherence to surveillance protocols, endoscopic detection of cancer foci in HDGc is suboptimal and imperfect for facilitating decision-making. Alternative endoscopic modalities, such as chromoendoscopy,endoscopic ultrasound, and other non-white light methods have been utilized,but are of limited utility to further improve cancer detection and risk stratification in HDGc. Herein, we review what is known and what remains unclear about endoscopic surveillance for HDGc, among individuals with and without germline cDH1 pathogenic variants. Ultimately, the use of endoscopy in the management of HDGc remains a challenging arena, but one in which further research to improve surveillance is crucial.

关键词： cDH1 gene Hereditary diffuse gastric cancer Gastric cancer Endoscopic screening Endoscopy