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Diagnostic value of amino acid consumption test on exocrine pancreatic insufficiency

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World journal of Gastroenterology 2000年第2期6卷 290-292页

作者： Lei ZM li DY li j Wang q He K Zheng SL Gan YG Luzhou Med Coll Affiliated Hosp Dept Hepatobiliary Surg Luzhou 646000 Sichuan Peoples R China

INTRODUCTIONAmino acid consumption test (AACT) has a highsensitivity and specificity in evaluating exocrinepancreatic insufficiency,but its diagnostic valueto exocrine pancreatic insufficiency in Chinese hasnot been well *** this study,the oralreagent stimulating pancreatic secretion (O-AACT)was used instead of cerulein(I-AACT) for amidoacid consumption test and the dignostic efficiency ofO-AACT was evaluated and compared with I-AACTon the exocrine pancreatic insufficiency in Chinese.

关键词： pancreatic insufficiency/diagnosis aminoacid consumption test cerulein cholelithiasis

DYNAMIC MODEL AND SIMULATION OF EAF STEELMAKING PROCESS

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 197-203页

作者： q.li X.Hong Shanghai Enhanced Laboratory of Ferrometallurgy Shanghai University Shanghai 200072 ChinaShanghai Enhanced Laboratory of Ferrometallurgy Shanghai University Shanghai 200072 China

Based on mass and energy balances and theories of thermodynamics and kinetics, a dynamic model in conjunction with relative operation parameters was derived. With this model, the EAF process in later stage of scarp melting was dynamically described, including time dependent variations of bath temperature, slag quantity, compositions of steel, slag and off-gas, etc. Steelmaking process in a domestic 100 ton UHP AC EAF was chosen as a computational example, and the simulated variations of temperature of hot metal and element contents was shown consistent with the actual process measurements within average error scopes of |△T| <15K, |[△A%C]| ≤ 0.036, |[△%Si]|≤0.00027, |[△%Mn]|≤0.002, |[△%P]|≤0.00089 and |[△%S]|≤0.001 respectively at the test points. The model will be extended to predict the whole production process including scrap melting procedure and evaluate its energy and material consumption, the production efficiency, etc., which will provide assistance for the improvement of EAF operation and control.

关键词： EAF dynamic model simulation

Novel flexible and transparent microstrip low-pass filter design with Π-shaped DGS

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The journal of China Universities of Posts and Telecommunications 2025年

作者： liu Zhaohan Han Yunan qiu Xianbo li Xianli College of Information Science and Technology， Beijing University of Chemical Technology

This paper proposes a new design for a transparent low-pass filter (LPF) using a flexible PTFE material and metallic copper. The transparent microstrip filter employs an asymmetric Π-shaped structure with dimensions of 260 mm × 13 mm × 0.148 mm， which owns a narrow transition band and achieves an insertion loss of less than 1.0 dB below 0.26 GHz. Furthermore， the insertion loss of the transparent microstrip filter can exceed 30 dB in the stopband of 1.02 GHz to 6.50 GHz. Square holes are added to the copper layer to improve the transparency of the LPF， and the filter performance can be adjusted by changing the square hole area and resolution. Additionally， multiple identical structures are cascaded to increase the insertion loss in the stopband while maintaining the passband. The transparent microstrip LPF has the characteristics of flexibility， high transparency， and significant insertion loss in the stopband， making it suitable for applications that require electromagnetic protection in a clear field of vision.

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Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China life Sciences 2025年第1期68卷 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng Yan Kun jiang Bingbing Song He li Maomao Cao Dianqin Sun Fan Yang Xinxin Yan Shaoli Zhang Yi Teng qianru li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrendlimited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

关键词： stomach neoplasms precancerous conditions cancer screening cumulative incidence risk stratification

Effect of Base Material on Microstructure and Texture Evolution of a Ti–6Al–4V Electron-Beam Welded joint

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 499-504页

作者： G.q.Wang Z.B.Zhao B.B.Yu j.R.liu q.j.Wang j.H.Zhang R.Yang j.W.li School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences Science and Technology on Power Beam Processes Laboratory Beijing Aeronautical Manufacturing Technology Research Institute

The effect of base material（BM） on microstructure and crystallographic orientation evolution of a Ti–6Al–4V electron-beam welded joint was investigated. Meanwhile, the crystallographic orientation of prior b grains was studied by advanced electron backscattered diffraction data processing. The inhomogeneity of microstructure within welded joint was formed due to the different microstructures of BM. By comparing microstructure details of the welded joint, including microstructure morphology and crystallographic orientation with those of the base material, it can be found that both the microstructure morphology and crystallographic orientation of the EBW joint would be controlled by BM.

关键词： Electron-beam welding Titanium alloys Prior b orientation Microstructure Texture

Multi-soliton solutions of a two-component Camassa–Holm system:Darboux transformation approach

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Communications in Theoretical Physics 2020年第4期72卷 23-28页

作者： Gaihua Wang Nianhua li q P liu Department of Mathematics China University of Mining and TechnologyBeiing100083China School of Mathematical Sciences Huaqiao UniversityQuanzhouFujian 362021China

We propose and develop another approach to constructing multi-soliton solutions of an integrable two-component Camassa–Holm(CH2)*** the help of a reciprocal transformation and a gauge transformation,we relate the CH2 system to a negative flow of the Broer–Kaup or twoboson *** solutions of this negative flow are given in terms of Wronskians via Darboux *** the multi-soliton solutions of the CH2 system are recovered in parametric form by inverting the reciprocal transformation and the gauge transformation.

关键词： Darboux transformation reciprocal transformation two-component Camassa–Holm system multi-soliton solutions

Mechanism transition of cross slip with stress and temperature in face-centered cubic metals

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journal of Materials Science & Technology 2020年第22期54卷 159-171页

作者： K.q.li Z.j.Zhang j.X.Yan j.B.Yang Z.F.Zhang Laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

A/2 screw dislocation is commonly dissociated into two /6 Shockley partial dislocations on{111} planes in face-centered cubic *** the two partials are not purely screw,different mechanisms of cross-slip could take place,depending on the stacking fault energy,applied stress and tempe *** is crucial to classify the mechanisms of cross-slip because each mechanism possesses its own reaction path with a special activation *** this work,molecular dynamics simulations have been performed systematically to explore the cross-slip mechanism under different stresses and temperatures in three different metals Ag,Cu and Ni that have different stacking fault energies of 17.8,44.4 and 126.8 mj/m^2,re *** Ag and Cu with low stacking fault energy,it is observed that the cross-slip mechanism of screw dislocations changes from the Fleischer obtuse angle(FLOA),to the Friedel-Escaig(FE),and then to the FL acute angle(FLAA) at low temperatures,with increasing the applied ***,when the temperature increases,the FE mechanism gradually becomes dominant,while the FLAA only occurs at the high stress *** particular,the FLOA has not been observed in Ni because of its high stacking fault energy.

关键词： Cross-slip Molecular dynamics simulation Face-centered cubic metals Stacking fault energy

THERMAL STRESSES RELAXATION DESIGN OF Ni/NiFe_(2)O_(4) SYSTEM FUNCTIONALLY GRADED CERMET INERT ANODE

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 635-641页

作者： j. li q.S. Zhang Y.q. Lai S.L. Ye Y.X. liu School of Metallurgy Science and Engineering Central South University Changsha 410083 China

The thermal stresses relaxation of Ni/NiFe2O4 system functionally graded cermet inert anode for aluminum electrolysis was optimally designed. The transient thermal stresses of the inert anode under complex boundary condition during high-temp （955℃） electrolysis were calculated using the finite-element software ANSYS, the influence of different parameters on the distribution of the thermal stresses were analyzed. The results showed that, during the process of thermal shock, the thermal hoop tensile stress on the surface of the anode is very large, which is possibly the major cause of anode crack; when the radius of the anode is between 0.05-0.15m, a range that can be realized by recent manufacturing technology, the optimum composition distribution exponent p is 0.25; The hoop tensile stresses reduce with the decrease of anode scale and also decrease with the decrease of the convection coefficient between the electrolyte and the anode.

关键词： functionally graded material (FGM) transient thermal stresses ANSYS inert anode aluminum electrolysis

Nonconforming FEMs for the p-Laplace Problem

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Advances in Applied Mathematics and Mechanics 2018年第6期10卷 1365-1383页

作者： D.j.liu A.q.li Z.R.Chen Department of Mathematics Shanghai UniversityShanghai 200444China

The p-Laplace problems in topology optimization eventually lead to a degenerate convex minimization problem E(v):=∫_(Ω)W(■v)dx-∫_(Ω)fvdx for v∈W_(0)^(1,p)(Ω)with unique minimizer u and stress s:=DW(ru).This paper proposes the discrete Raviart-Thomas mixed finite element method(dRT-MFEM)and establishes its equivalence with the Crouzeix-Raviart nonconforming finite element method(CR-NCFEM).The sharper quasi-norm a priori and a posteriori error estimates of this two methods are *** experiments are provided to verify the analysis.

关键词： Adaptive finite element methods nonconforming p-Laplace problem dual energy