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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui Zhang Xue-Qi Wang Qian sun Chen Zhang Yu Li Zhuohua sun Katalin Barta Feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science China Chemistry 2025年第1期68卷 181-185页

作者： Yanping Xia Luyang sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

关键词： aliphatic ketones ketyl radical intermolecular cross-coupling tertiary alcohols

2D CaWO4 nanosheets derived from scheelite minerals for enhanced electrocatalysis in oxygen evolution reaction

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Science China Chemistry 2025年

作者： Qing sun Yongxiang sun Yan Dong Hong Zhong Hongbo Zeng National&Local United Engineering Laboratory for New Petrochemical Materials&Fine Utilization of Resources College of Chemistry and Chemical EngineeringHunan Normal University Department of Chemical and Materials Engineering University of Alberta College of Chemistry and Materials Engineering Hunan University of Arts and Science College of Chemistry and Chemical Engineering Central South University

Scheelite （CaWO4） mineral holds promise as a cost-effective and efficient catalyst for the oxygen evolution reaction （OER）crucial in renewable energy ***,challenges such as limited active site exposure and low electrocatalytic performance need *** this work,we have fabricated two-dimensional （2D） CaWO4nanosheets from scheelite minerals via a straightforward ultrasonic exfoliation method and evaluated their efficacy as OER *** to scheelite powders,these 2D nanosheets exhibited superior crystallinity and a 1.26-fold increase in electrochemical surface area,promoting active site *** 2D CaWO4nanosheet electrode demonstrated outstanding OER catalytic performance,achieving a current density of 20 mA/cm2at an overpotential of 290 m V in alkaline conditions,which was lower than that of bulk CaWO4electrodes （～340 mV）.Density functional theory calculations attributed this enhanced catalytic performance to moderate adsorption of oxygenated intermediates （*OH,*O,and*OOH） on the W sites of 2D *** situ electrochemical atomic force microscopy tests also confirmed the catalytic enhancement by 2D CaWO4nanosheets during *** findings demonstrate the potential of affordable and abundant mineral resources in advancing electrochemical catalysts for oxygen evolution,highlighting their broader application in sustainable energy technologies.

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Study on contact fatigue of a wind turbine gear pair considering surface roughness

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Friction 2020年第3期8卷 553-567页

作者： Heli LIU Huaiju LIU Caichao ZHU Zhangdong sun houyi BAI State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400030China Hubei University of Automotive Technology Shiyan 442002HubeiChina Chongqing Wangjiang Industrial Co.Chongqing 400071China

Contact fatigue issues become more and more crucial in gear industry as they significantly affect the reliability and service life of associated mechanical systems such as wind turbine *** contact fatigue behavior is mostly determined by the mechanical properties of materials and stress fields near the contact area,which is further influenced by the lubrication and surface roughness due to pressure *** this study,a numerical model incorporating the lubrication state,tooth surface roughness,residual stress,and mechanical properties of the material is developed to determine the contact fatigue behavior of a megawatt level wind turbine carburized *** variations of the hardness and residual stress along the depth were characterized by the Vickers hardness measurement and X-ray diffraction test,*** elastohydrodynamic lubrication theory was applied to predict the contact pressure distribution,highlighting the influence of the surface roughness that stemed from the original measurement through an optical *** stress histories of the studied material points during a complete contact loading cycle were fast calculated using the discreteconcrete fast Fourier transformation(DC-FFT)*** Dang Van diagrams under different working conditions were determined to estimate the contact fatigue failure *** effect of the root mean square(RMS)value of the surface roughness on the failure risk at critical material points were discussed in *** revealed that the surface roughness significantly increases the contact fatigue failure risk within a shallow area,and the maximum risk appears near the surface.

关键词： carburized gear contact fatigue surface roughness residual stress Dang Van criterion

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鸿鹄机器人辅助全膝关节置换的早期学习曲线

山东大学学报（医学版） 2023年第3期61卷 115-120页

作者：郭永园孙厚义张元凯颜廷宾刘培来贾玉华山东大学齐鲁医院骨科山东济南250012

目的回顾性分析鸿鹄骨科机器人辅助人工膝关节置换(TKA)的手术时间和影像学数据,探讨机器人辅助TKA的临床效果和学习曲线。方法对同一手术组开展的25例机器人辅助TKA手术进行分析,将手术时间通过累积和分析法(CUSUM)进行分析,绘制机器... 详细信息

目的回顾性分析鸿鹄骨科机器人辅助人工膝关节置换(TKA)的手术时间和影像学数据,探讨机器人辅助TKA的临床效果和学习曲线。方法对同一手术组开展的25例机器人辅助TKA手术进行分析,将手术时间通过累积和分析法(CUSUM)进行分析,绘制机器人辅助TKA的学习曲线,根据学习曲线分为两个不同阶段,比较两个阶段的手术时间、出血量、住院天数、髋-膝-踝角等影像学数据和临床评分。结果CUSUM分析结果显示,机器人辅助TKA的学习曲线最大转折点在第13例手术,基于此将学习曲线划分为学习提高阶段和熟练掌握阶段,两个阶段患者的一般资料、术后髋-膝-踝角等影像学数据、美国特种医院(HSS)评分、膝关节活动范围(ROM)和关节置换术后忘记评分(FSJ-12)差异无统计学意义(P>0.05),但熟练掌握阶段与学习提高阶段相比,整体手术时间减少23 min,空间摆位时间下降4.4 min,光学靶标安装下降5.0 min;在手术操作平均耗时上,定位下肢力线和关节面配准的时间分别降低2.9 min和5.2 min,机械臂截骨操作时间降低14.1 min。结论利用CUSUM方法准确分析了机器人辅助TKA的学习曲线,显示熟练掌握操作此技术须累积的手术例数为13例。机器人辅助TKA学习曲线短,临床效果满意。

关键词：机器人人工膝关节置换学习曲线临床效果影像学测量

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Efficient OpenMP Based Z-curve Encoding and Decoding Algorithms

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Computers, Materials & Continua 2025年第1期82卷 1313-1327页

作者： Zicheng Zhou Shaowen sun Teng Liang Mengjuan Li Fengling Xia School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China School of Communications Information Engineering Yunnan Communications Vocational and Technical CollegeKunming650500China Library Yunnan Normal UniversityKunming650500China Faculty of Civil Aviation and Aeronautics Kunming University of Science and TechnologyKunming650500China

Z-curve’s encoding and decoding algorithms are primely important in many Z-curve-based *** bit interleaving algorithm is the current state-of-the-art algorithm for encoding and decoding *** simple,its efficiency is hindered by the step-by-step coordinate shifting and bitwise *** tackle this problem,we first propose the efficient encoding algorithm LTFe and the corresponding decoding algorithm LTFd,which adopt two optimization methods to boost the algorithm’s efficiency:1)we design efficient lookup tables(LT)that convert encoding and decoding operations into table-lookup operations;2)we design a bit detection mechanism that skips partial order of a coordinate or a Z-value with consecutive 0s in the front,avoiding unnecessary iterative *** propose order-parallel and point-parallel OpenMP-based algorithms to exploit the modern multi-core *** results on discrete,skewed,and real datasets indicate that our point-parallel algorithms can be up to 12.6×faster than the existing algorithms.

关键词： Z-curve lookup table OpenMP bit detection mechanism

Ubiquitin-specific protease 1 facilitates tumor immune escape from natural killer cells and predicts the prognosis in small cell lung cancer

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Oncology Research 2025年第1期33卷 213-224页

作者： SHIQIN JIANG YICHUN TANG FENG MA YUCHUN NIU LEI sun Department of Clinical Pharmacy Shenzhen Hospital of Integrated Traditional Chinese and Western MedicineShenzhen518104China Department of Pathology Zhujiang HospitalSouthern Medical UniversityGuangzhou510280China Department of Radiation Oncology The First People’s Hospital of FoshanFoshan528000China Department of Oncology The First Affiliated Hospital of Jinan UniversityJinan UniversityGuangzhou510630China Department of Oncology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguan523721China

Objective:Small cell lung cancer(SCLC)is commonly recognized as the most fatal lung cancer *** substantial advances in immune checkpoint blockade therapies for treating solid cancers,their benefits are limited to a minority of patients with *** the present study,novel indicators for predicting the outcomes and molecular targets for SCLC treatment were ***:We conducted bioinformatics analysis to identify the key genes associated with tumor-infiltrating lymphocytes in *** functional role of the key gene identified in SCLC was determined both in vitro and in ***:A significant correlation was observed between patient survival and CD56dim natural killer(NK)cell ***,we noted that the hub gene ubiquitin-specific protease 1(USP1)is closely correlated with both CD56dim NK cells and overall survival in *** analysis revealed that USP1 is upregulated in *** addition,gene set enrichment analysis revealed that USP1 overexpression hinders NK cell-mediated immune *** co-cultivating NK-92 cells with SCLC cells,we demonstrated that NK cell cytotoxicity against SCLC could be improved either via USP1 knock-down or pharmacological ***,using a nude-mice xenograft tumor model,we noted that USP1 inhibition effectively suppressed tumor proliferation and increased the expression of NK cell-associated ***:Our study findings highlight the importance of NK cells in regulating ***1 overexpression can inhibit NK cell-mediated immunity;therefore,USP1 may serve not only as a prognostic biomarker but also as a potential molecular target of SCLC therapy.

关键词： Ubiquitin-specific protease 1(USP1) Natural killer(NK)cell Small cell lung cancer(SCLC) Prognosis Immune escape

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin Peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

Occluded Gait Emotion Recognition Based on Multi-Scale Suppression Graph Convolutional Network

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Computers, Materials & Continua 2025年第1期82卷 1255-1276页

作者： Yuxiang Zou Ning He Jiwu sun Xunrui Huang Wenhua Wang Beijing Key Laboratory of Information Service Engineering Beijing Union UniversityBeijing100101China College of Smart City Beijing Union UniversityBeijing100101China

In recent years,gait-based emotion recognition has been widely applied in the field of computer ***,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is *** enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation *** MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait *** SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition *** proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other ***,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods.

关键词： KNN interpolation multi-scale temporal convolution suppression graph convolutional network gait emotion recognition human skeleton