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Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

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Petroleum Science 2024年第4期21卷 2329-2344页

作者： Jiu-Qiang yang Nian-Tian lin kai Zhang yan Cui Chao Fu Dong Zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction

Corrosion behavior of Gd_(2)Zr_(2)O_(7)thermal barrier coatings under Fe-containing environmental sediment attack

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Journal of Advanced Ceramics 2024年第4期13卷 447-462页

作者： Lei Guo yanyan Li kai yan School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Advanced Joining Technology Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin 300072China Key Laboratory of Special Equipment Safety and Energy-saving for State Market Regulation China Special Equipment Inspection&Research InstituteBeijing 100029China

Environmental sediments mainly consisting of CaO–MgO–Al_(2)O_(3)–SiO_(2)(CMAS)corrosion are a serious threat to thermal barrier coatings(TBCs),in which Fe element is usually ***_(2)Zr_(2)O_(7)TBCs are famous for their excellent CMAS *** this study,the characteristics of Fe-containing environmental sediments(CMAS-Fe)and their corrosiveness to Gd_(2)Zr_(2)O_(7)coatings were *** types of CMAS-Fe glass with different Fe contents were *** melting points were measured to be 1322–1344℃,and the high-temperature viscosity showed a decreasing trend with increasing Fe *** corrosion behavior of four types of CMAS-Fe to Gd_(2)Zr_(2)O_(7)coatings at 1350℃was *** the initial corrosion stage(0.1 h),anorthite was precipitated in CMAS-Fe with a high Ca:Si ratio,while Fe-garnet was formed in the melt with the highest Fe *** the corrosion time resulted in the formation of a reaction layer,which exhibited an interpenetrating network composed of Gd-oxyapatite,ZrO_(2),and residual *** spinel was precipitated within the reaction *** 1 h or even longer time,the reaction layers tended to be stable and compact,which had comparable hardness and fracture toughness to those of Gd_(2)Zr_(2)O_(7)*** the cyclic CMAS-Fe attack,the residual CMAS-Fe in the interpenetrating network provided a pathway for the redeposited CMAS-Fe infiltration,resulting in the continuous growth of the reaction *** a result,the Gd_(2)Zr_(2)O_(7)coatings had a large consumption in the thickness,degrading the coating ***,the Gd_(2)Zr_(2)O_(7)coatings exhibit unsatisfactory corrosion resistance to CMAS-Fe attack.

关键词： thermal barrier coatings(TBCs) Gd_(2)Zr_(2)O_(7) Fe-containing CaO-MgO-Al2O3-SiO_(2)(CMAS) corrosion resistance reaction layer

Adaptive admittance tracking control for interactive robot with prescribed performance

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Journal of Systems Engineering and Electronics 2024年第2期35卷 444-450页

作者： MENG Qingrui lin yan School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100190China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights,demonstrating the viability of the control scheme proposed in this paper.

关键词： prescribed performance admittance control adaptive control robots

Thermal Decomposition and Oxidative Decomposition Mechanism of HFC-134a by Experimental and DFT Method

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Journal of Thermal Science 2024年第5期33卷 1990-2003页

作者： XU Yunting ZHANG kai DAI Xiaoye SHI lin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

In response to the Kigali Amendment to the Montreal Protocol and global low-carbon emission environmental requirements,the phase-out and decomposition of numerous HFC refrigerants have become urgent,necessitating efficient and mild decomposition *** study investigates the thermal decomposition and oxidative thermal decomposition pathways of the typical hydrofluorocarbon refrigerant HFC-134a,employing a combination of experimental and quantum chemical DFT simulation *** chemical simulations reveal that the initial reaction bond cleavage serves as the rate-determining step during the thermal decomposition process,with the most easily detectable closed-shell products including CF_(2)=CHF,HF,CH_(3)F,CHF_(3),CH_(2)F_(2),and CF_(4).Reactive oxygen species can significantly reduce the Gibbs free energy barrier for HFC-134a *** achieve efficient degradation of HFC-134a,appropriate catalysts should be developed and selected to increase the level of reactive oxygen species in the reaction *** studies further corroborate that HFC-134a may undergo degradation through distinct reaction pathways under varying temperature(240℃to360℃)and pressure(0.1 MPa to 4.5 MPa)conditions,in agreement with simulation predictions.

关键词： HFC-134a pyrolysis oxidative thermal decomposition DFT refrigerant

Coexistence of liver abscess, hepatic cystic echinococcosis and hepatocellular carcinoma: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2404-2411页

作者： Ya-Wen Hu Yi-lin Zhao Jing-Xin yan Cun-kai Ma Department of Interventional Therapy The Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina West China Hospital Sichuan UniversityChengdu 610000Sichuan ProvinceChina

BACKGROUND Human cystic echinococcosis(CE)is a life-threatening zoonosis caused by the Echinococcus granulosus(sensu lato).Hepatocellular carcinoma(HCC)is a leading cause of cancer-related mortality in the *** coexistence of CE and HCC is exceedingly rare,and only several well-documented cases have been *** addition to this coexistence,there is no report of the coexistence of CE,HCC,and liver abscess to ***,we aimed to report a case of coexistence of liver abscess,hepatic CE,and *** SUMMARY A 65-year-old herdsman presented to the department of interventional therapy with jaundice,right upper abdominal distension and pain for 10 *** test showed that he had positive results for HBsAg,HBeAb,HBcAb,and echino-coccosis IgG *** test also showed an increased level of alpha fetopro-tein of 3400 ng/*** abdominal computed tomography(CT)scan revealed an uneven enhanced lesion of the liver at the arterial phase with enhancement and was located S4/8 segment of the *** addition,CT scan also revealed a mass in the S6 segment of the liver with a thick calcified wall and according to current guideline and medical images,the diagnoses of hepatic CE(CE4 subtype)and HCC were ***,transarterial chemoembolization was performed for *** the follow-up,liver abscess occurred in addition to CE and HCC;thus,percutaneous liver puncture drainage was *** the next follow-up,CE and HCC were *** liver abscess was completely resolved,and the patient was discharged with no evidence of *** This is the first reported case on the coexistence of liver abscess,hepatic CE,and *** treatment and multidisciplinary discussions should be performed in this ***,treatment and diagnosis should be based on the characteristics of liver abscess,hepatic CE,and HCC,and in future clinical work,it is necessary to be aware of the possibility of this complex composition of liver diseases.

关键词： Cystic echinococcosis Hepatocellular carcinoma Liver abscess Multidisciplinary discussions Case report

Synthesis and characteristics of transparent Gd_(2)O_(3)ceramics with cubic structure

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Journal of Advanced Ceramics 2024年第4期13卷 463-468页

作者： Akio Ikesue yan lin Aung World Lab Co. Nagoya456-8587Japan

Transparent Gd_(2)O_(3)ceramics with a cubic crystal structure were successfully synthesized for the first *** Gd_(2)O_(3)ceramics subjected to hot isostatic press(HIP)at 1070℃consisted of uniform grains of 2-3μm,and only a few residual pores could be detected inside the materials.X-ray diffraction(XRD)shows that the obtained polycrystalline materials have a cubic crystal structure,and the transmission polarized light observation shows that there is no birefringence inside the materials,indicating inherent optical properties of the cubic crystal *** optical absorption edge is 640 nm(optical band gap:2.1 eV),and the transmittance in the visible to near-infrared region is 72%,which is close to the theoretical transmittance calculated from Fresnel *** constant of this material is almost wavelength-independent,and it is diamagnetic since it has the opposite polarity to that of common paramagnetic materials.

关键词： gadolinium oxide cubic hot isostatic press(HiP) diamagnetic Verdet constant

Graphitic carbon nitride nanosheets mitigate cadmium toxicity in Glycine max *** promoting cadmium retention in root and improving photosynthetic performance

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Journal of Environmental Sciences 2024年第5期139卷 543-555页

作者： kai Xu Yunyu Guo Chenghua Xing Ronglong Fu Bin Zou Rongchuan Liu Luyi Cai Jianfang yan Xi-lin Wu Miaozhen Cai College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China College of Agriculture Jinhua PolytechnicJinhua 321007China

Cadmium(Cd)pollution poses a serious threat to plant growth and *** have shown great application potential for alleviation of Cd toxicity to *** this study,we applied graphitic carbon nitride nanosheets(g-C_(3)N_(4)NSs)for alleviation of Cd-toxicity to soybean(Glycine max L.).The g-C_(3)N_(4)NSs supplementation significantly improved plant growth and reduced oxidative damage in the Cd-toxicated soybean seedlings through hydroponic ***,the g-C_(3)N_(4)NSs dynamically regulated the root cell wall(RCW)components by increasing pectin content and modifying its demethylation via enhancing pectin methylesterase(PME)activity,therefore greatly enhanced stronger RCW-Cd retention(up to 82.8%)and reduced Cd migration to the ***,the g-C_(3)N_(4)NSs reversed the Cd-induced chlorosis,increased photosynthetic efficiency because of enhancement in F_v/F_mration,Y(Ⅱ)and sugars *** results provide new insights into the alleviation of Cd toxicity to plants by g-C_(3)N_(4)NSs,and shed light on the application of low-cost and environmental-friendly carbon-based NMs for alleviating heavy metal toxicity to plants.

关键词： Cadmium Carbon nitride nanosheets Cell wall Pectin Pectin methylesterase Soybean

Flexible Crystal Heterojunctions of Low-Dimensional Organic Metal Halides Enabling Color-Tunable Space-Resolved Optical Waveguides

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Research 2024年第3期6卷 293-304页

作者： Yuhang lin Shuya Liu Dongpeng yan Beijing Key Laboratory of Energy Conversion and Storage Materials and Key Laboratory of RadiopharmaceuticalsMinistry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China.

Molecular luminescent materials with optical waveguide have wide application prospects in light-emitting diodes, sensors, and logic gates. However, the majority of traditional optical waveguide systems are based on brittle molecular crystals, which limited the fabrication, transportation, storage, and adaptation of flexible devices under diverse application situations. To date, the design and synthesis of photofunctional materials with high flexibility, novel optical waveguide, and multi-port color-tunable emission in the same solid-state system remain an open challenge. Here, we have constructed new types of zero-dimensional organic metal halides (Au-4-dimethylaminopyridine [DMAP] and In-DMAP) with a rarely high elasticity and rather low loss coefficients for optical waveguide. Theoretical calculations on the intermolecular interactions showed that the high elasticity of 2 molecular crystalline materials was original from their herringbone structure and slip plane. Based on one-dimensional flexible microrods of 2 crystals and the 2-dimensional microplate of the Mn-DMAP, heterojunctions with multi-color and space-resolved optical waveguides have been fabricated. The formation mechanism of heterojunctions is based on the surface selective growth on account of the low lattice mismatch ratio between contacting crystal planes. Therefore, this work describes the first attempt to the design of metal-halide-based crystal heterojunctions with high flexibility and optical waveguide, expanding the prospects of traditional luminescent materials for smart optical devices, such as logic gates and multiplexers.

关键词： waveguide Crystal elasticity

Beyond 1,4-addition of in-situ generated(aza-)quinone methides and indole imine methides

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Chinese Chemical Letters 2024年第7期35卷 35-53页

作者： yan-Li Li Zhi-Ming Li kai-kai Wang Xiao-Long He Medical College Xinxiang UniversityXinxiang 453000China School of Pharmacy Xinxiang UniversityXinxiang 453000China School of Food and Bioengineering Xihua UniversityChengdu 610039China

The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and *** alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid *** relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,***,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative *** conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past *** review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs.

关键词： Conjugate addition QMs IIMs LUMO Remote activation Dearomative addition