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Unexpected/contrary behavior of aerosol mass concentration in response to the individual components'concentration reduction in Kitakyushu,Japan

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Journal of Environmental Sciences 2024年第1期135卷 630-639页

作者： xi Zhang Takuya Murakami Jinhe wang Masahide Aikawa Faculty of Environmental Engineering The University of Kitakyushu1-1HibikinoWakamatsuKitakyushuFukuoka 808-0135Japan Resources and Environment Innovation Research Institute School of Municipal and Environmental EngineeringShandong Jianzhu UniversityJinan 250101China

In the suburbs of Kitakyushu,Japan,the inorganic aerosol mass concentration(IAM)was about 32.7μg/m^(3),with the aerosol pH of 3.3.To study the thermodynamics of aerosol when its individual components'concentration is reduced,sensitive tests were performed using the ISORROPIAⅡmodel,in which the seven control species—TNaCl,TNH_(4)^(+),TSO_(4)^(2-),TNO_(3)^(-),TMg^(2+),TK^(+),and TCa^(2+)—were taken into account.IAM and inorganic aerosol pH after reducing TNaCl,TNO_(3)^(-),TMg^(2+),TK^(+),and TCa^(2+)responded linearly(0%≤concentration reduction ratio(CRR)≤100%,with the exception of 100%in TNaCl);the nonlinear variations of these two parameters could be observed by controlling TNH_(4)^(+)and TSO_(4)^(2-).Unexpected aerosol behavior occurred at 100%reduction of TNaCl,which was caused by the sudden increase of NO_(3)^(-),NH_(4)^(+),and aerosol liquid water content(ALWC);the increase of IAM was also observed after controlling TSO_(4)^(2-)(60%≤CRR≤100%)and TCa^(2+)(0%≤CRR≤100%),which was mainly related to the variation of ALWC driven by the response of CaSO_(4).Multiple regression analysis showed that ALWC was statistically and strongly related to the variations of NO_(3)^(-),Cl-,SO_(4)^(2-),HSO_(4)^(-),HNO_(3),and NH_(3)(P<0.05),with regression coefficients of 1.68,5.23,1.83,2.81,0.34,and 0.57,respectively.The highest coefficient(5.23)was found for Cl^(-),revealing that sea salts significantly influenced particle responses.Overall,this study comprehensively investigated aerosol characteristics and inner responses for the reduction of components,which is of great significance for a better understanding of atmospheric chemistry in Kitakyushu,Japan.

关键词： Sensitive tests Reduction Gas-particle conversion process Aerosol liquid water content Sea salts

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High-Efficiency Wideband Transmitarray Antenna Using Polarization-Rotating Elements with Parasitic Stubs

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Chinese Journal of Electronics 2024年第2期33卷 496-503页

作者： xi wang Yuandan DONG University of Electronic Science and Technology of China

A high-efficiency polarization-rotating transmitarray antenna(TA) using wideband elements is proposed for millimeter-wave applications. The polarization-rotating element consists of three metallic layers and two substrates. Orthogonal polarizers are employed on the top and bottom of the element. And the split ring with a parasitic stub on the middle layer is symmetric about the diagonal, performing the polarization rotation and phase compensation simultaneously. A parasitic stub is designed to decrease transmission loss and broaden the bandwidth. The periodicity of the element is only 1/4 wavelength at 30 GHz. A prototype TA with 28 × 28 elements is designed, fabricated, and measured. The measured peak gain reaches 27.5 d Bi at 37.8 GHz. The 1-d B gain drop bandwidth is 30.8–40 GHz(26.0%).The aperture efficiency reaches as high as 71% at 31.5 GHz. Within the bandwidth of 26.5–38.8 GHz(37.7%), the aperture efficiency is higher than 50%. The proposed polarization-rotating TA features wide bandwidth and high efficiency, demonstrating great application potential for 5G millimeter-wave communication.

关键词： High-efficiency Lens antenna Millimeter-wave Polarization rotation Transmitarray antenna Wideband antenna

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Liquid metal biomaterials: translational medicines,challenges and perspectives

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National Science Review 2024年第2期11卷 264-284页

作者： Hanchi Xu Jincheng Lu Yikuang xi Xuelin wang Jing Liu Department of Biomedical Engineering School of Medicine Tsinghua University Beijing Tsinghua Changgung Hospital School of Clinical Medicine Tsinghua University Shanghai World Foreign Language Academy Beijing Advanced Innovation Center for Biomedical Engineering School of Engineering MedicineBeihang University Beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Until now, significant healthcare challenges and growing urgent clinical requirements remain incompletely addressed by presently available biomedical materials. This is due to their inadequate mechanical compatibility, suboptimal physical and chemical properties, susceptibility to immune rejection, and concerns about long-term biological safety. As an alternative, liquid metal(LM) opens up a promising class of biomaterials with unique advantages like biocompatibility, flexibility, excellent electrical conductivity,and ease of functionalization. However, despite the unique advantages and successful explorations of LM in biomedical fields, widespread clinical translations and applications of LM-based medical products remain limited. This article summarizes the current status and future prospects of LM biomaterials, interprets their applications in healthcare, medical imaging, bone repair, nerve interface, and tumor therapy, etc.Opportunities to translate LM materials into medicine and obstacles encountered in practices are discussed.Following that, we outline a blueprint for LM clinics, emphasizing their potential in making new-generation artificial organs. Last, the core challenges of LM biomaterials in clinical translation, including bio-safety,material stability, and ethical concerns are also discussed. Overall, the current progress, translational medicine bottlenecks, and perspectives of LM biomaterials signify their immense potential to drive future medical breakthroughs and thus open up novel avenues for upcoming clinical practices.

关键词： liquid metal biomaterials translational medicine clinical device healthcare therapeutics

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Nanofluidic memristor based on the elastic deformation of nanopores with nanoparticle adsorption

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National Science Review 2024年第4期11卷 46-54页

作者： xi Zhou Yuanyuan Zong Yongchang wang Miao Sun Deli Shi Wei wang Guanghua Du Yanbo xie Department of Chemistry and Chemical Engineering Northwestern Polytechnical University School of Physical Science and Technology Northwestern Polytechnical University School of Aeronautics and Institute of Extreme Mechanics Northwestern Polytechnical University Institute of Modern Physics Chinese Academy of Sciences

The memristor is the building block of neuromorphic computing. We report a new type of nanofluidic memristor based on the principle of elastic strain on polymer nanopores. With nanoparticles absorbed at the wall of a single conical polymer nanopore, we find a pinched hysteresis of the current within a scanning frequency range of 0.01–0.1 Hz, switching to a diode below 0.01 Hz and a resistor above 0.1 Hz. We attribute the current hysteresis to the elastic strain at the tip side of the nanopore, caused by electrical force on the particles adsorbed at the inner wall surface. Our simulation and analytical equations match well with experimental results, with a phase diagram for predicting the system transitions. We demonstrate the plasticity of our nanofluidic memristor to be similar to a biological synapse. Our findings pave a new way for ionic neuromorphic computing using nanofluidic memristors.

关键词： nanofluidics memristor neurocomputing elastic deformation

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High-responsivity on-chip waveguide coupled germanium photodetector for 2 μm waveband

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Photonics Research 2024年第1期12卷 115-122页

作者： JIANING wang xi wang YIHANG LI YANFU YANG QINGHAI SONG KE XU Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Harbin Institute of TechnologyShenzhen 518055China Department of Electronic&Information Engineering Harbin Institute of TechnologyShenzhen 518055China Department of Science Harbin Institute of TechnologyShenzhen 518055China

Recently,the emerging 2μm waveband has gained increasing interest due to its great potential for a wide scope of applications.Compared with the existing optical communication windows at shorter wavelengths,it also offers distinct advantages of lower nonlinear absorption,better fabrication tolerance,and larger free carrier plasma effects for silicon photonics,which has been a proven device technology.While much progress has been witnessed for silicon photonics at the 2μm waveband,the primary challenge still exists for on-chip detectors.Despite the maturity and compatibility of the waveguide coupled photodetectors made of germanium,the 2μm regime is far beyond its cutoff wavelength.In this work,we demonstrate an efficient and high-speed on-chip waveguidecoupled germanium photodetector operating at the 2μm waveband.The weak sub-bandgap absorption of epitaxial germanium is greatly enhanced by a lateral separation absorption charge multiplication structure.The detector is fabricated by the standard process offered by a commercial foundry.The device has a benchmark performance with responsivity of 1.05 A/W and 3 dB bandwidth of 7.12 GHz,which is able to receive high-speed signals with up to 20 Gbit/s data rate.The availability of such an efficient and fast on-chip detector circumvents the barriers between silicon photonic integrated circuits and the potential applications at the 2μm waveband.

关键词： waveguide responsivity wave

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Predication of Selective Ring-opening Hydrogenolysis for Furfuryl Alcohol to Produce Pentanediol over Dual-atom Catalysts

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Chemical Research in Chinese Universities 2024年第1期40卷 55-63页

作者： wang Tingting wang Jia xi Yongjie HU Bin LI Fuwei State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Selective activation of C-O bond is of fundamental importance in the precise conversion of oxygenates into value-added compounds in an atom-economic and sustainable manner, and meanwhile, the structurally well-defined dual-atoms catalysts (DACs) have been scarcely investigated in this field. In this study, a series of transition metal DACs anchored on nitrogen-doped graphene (TM2/NC, TM=Pt, Ir, Rh, Pd, Ru, Co, Ni and Cu) was constructed to make a comprehensive investigation of their selectivity in the hydrogenative transformation of furfuryl alcohol (FAL), an important biomass platform molecule, to 1,2-pentanediol (1,2-PeD) via selective cleavage of furanic C5-O bond, by density functional theory (DFT) calculations and microkinetic modeling. We found that Ir2/NC demonstrated a high selectivity for the cleavage of furanic C5-O bond to produce 1,2-PeD, while the production of THFAL or 1,5-pentanediol (1,5-PeD) on other TM2/NC catalysts are more favorable. Furthermore, we found that the selective C-O bond cleavage of FAL furan ring is affected by the orbital overlap between the d-orbitals of the anchored metal atoms and the p-orbitals of the adsorbed C atom in FAL, suggesting that the selectivity of the C-O bond cleavage is inextricably related with the electronic property of the anchored metals.

关键词： Furfuryl alcohol Hydrogenation Dual-atom catalyst Density functional theory(DFT)calculation

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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries

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Horticultural Plant Journal 2024年第3期10卷 713-731页

作者： Haining Yin Zhaoxiang wang Lin wang Jianhong Cao Jiakui wang Zhumei xi College of Enology Northwest A&F UniversityYanglingShaanxi 712100China Shangri-la Winery Co. LTDShangri-laYunnan 674400China

Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards.

关键词： Vitis vinifera L. Orientated rows Berry composition Sugar Phenolic Light quality Solar radiation

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Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： Jin-xi Zhang Kai-Di Xu Qing-Guo wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

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Synthesis of Anti-Pancreatic Cancer Natural Product Majusculamide D and Analogues Reveals a Preliminary Structure-Activity Relationships

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Chinese Journal of Chemistry 2024年第6期42卷 605-610页

作者： xiuhe Zhao Mengxue Lv xiaonan xi Yaxin Lu Liang wang Yue Chen The State Key Laboratory of Medicinal Chemical Biology College of PharmacyNankai UniversityTianjin300350 China College of Chemistry Nankai UniversityTianjin300071 China

The total synthesis of majusculamide D(1)was achieved from commercially available materials.In addition,we synthesized eight analogues including three stereoisomers of majusculamide D that differ in the fatty acid chain.Six analogues including a simplified analogue 29 exhibited significant nanomolar-level IC50 values against Panc-1 cells in MTT assays.A preliminary SAR analysis indicated that the hydroxyl group at C10 and C2−C3 unsaturated double bond of majusculamide D were essential in maintaining the high activity against Panc-1 cells and the orientation of C40-Me and C42-Me groups was tolerable.

关键词： Majusculamide D Natural products SAR Anti-pancreatic cancer Lipopentapeptide

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Pyruvate kinase M in germ cells is essential for sperm motility and male fertility but not spermatogenesis

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Asian Journal of Andrology 2024年第2期26卷 212-219页

作者： Gao-Qing Qian xiao-Chen wang xi Zhang Bin Shen Qiang Liu State Key Laboratory of Reproductive Medicine and Offspring Health Nanjing Medical UniversityNanjing 211166China Shanghai Key Laboratory of Reproductive Medicine Department of HistoembryologyGenetics and Developmental BiologyShanghai Jiao Tong University School of MedicineShanghai 200025China State Key Laboratory of Molecular Biology Shanghai Key Laboratory of Molecular AndrologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200031China

Male germ cells employ specific metabolic pathways throughout their developmental stages.In a previous study,we discovered heightened expression of pyruvate kinase M(PKM),a pivotal glycolytic enzyme,in spermatogonia and spermatids.To gain deeper insights into PKM's roles in spermatogenesis,sperm function,and male fertility,we engineered a conditional-knockout mouse model(Pkm-vkO mice)to selectively disrupt the Pkm gene within germ cells.Despite maintaining regular testicular histology and sperm morphology,the male Pkm-vko mice were infertility,characterized by significant impairments in sperm motility and adenosine triphosphate(ATP)generation.In addition,Pkm-null spermatozoa exhibited similar deficits in protein tyrosine phosphorylation linked to capacitation,as well as compromised performance in in vitro fertilization experiments.To conclude,PKM's presence is not obligatory for the entirety of spermatogenesis in male germ cells;however,it emerges as a critical factor influencing sperm motility and overall male fertility.

关键词： glycolysis male fertility pyruvate kinase M sperm motility spermatogenesis

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