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Nuclear volume effects in kinetic isotope fractionation:A case study of mercury oxidation by chlorine species

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Acta Geochimica 2024年第3期43卷 411-423页

作者： Chenlu yang Yining Zhang yun Liu Research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

It is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MIFs).However,the effect of the NVE on these kinetic processes is not *** total fractionations(MDFs+NVEinduced MIFs)of several representative Hg-incorporated substances were selected and calculated with ab initio calculations in this work for both equilibrium and kinetic ***-induced MIFs were calculated with scaled contact electron densities at the nucleus through systematic evaluations of their accuracy and errors using the Gaussian09 and DIRAC19 packages(named the electron density scaling method).Additionally,the NVE-induced kinetic isotope effect(KIE)of Hg isotopes are also calculated with this method for several representative Hg oxidation reactions by chlorine *** KIEs for 2.2.Hg/^(198)Hg ranging from−2.2.‰to 0.96‰are *** anomalous^(2.2.Hg-enriched KIEs(δ^(2.2.Hg/^(198)Hg=0.83‰,0.94‰,and 0.96‰,)caused by the NVE are observed,which are quite different from the classical view(i.e.,light isotopes react faster than the heavy ones).The electron density scaling method we developed in this study can provide an easier way to calculate the NVE-induced KIEs for heavy isotopes and serve to better understand the fractionation mechanisms of mercury isotope systems.

关键词： Nuclear volume effect Kinetic fractionation Hg isotopes Ab initio calculations

Review on birefringence in borates based on birefringence-active functional groups and arrangements

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Science China Chemistry 2024年第7期67卷 2155-2170页

作者： Qianzhen Zhang Ran An Zhihua yang Xifa Long Shilie Pan yun yang Research Center for Crystal Materials State Key Laboratory of Functional Materials and Devices for Special Environmental ConditionsXinjiang Key Laboratory of Functional Crystal MaterialsThe Xinjiang Technical Institute of Physics&ChemistryChinese Academy of SciencesUrumqi 830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the nonlinear optical *** big birefringence not only benefits to the miniaturization of related devices,but also broadens the phase-matching wavelength range of nonlinear optical *** design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology ***,crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups,and the relationship between structure and properties is thoroughly *** is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence.

关键词： birefringence borate optical functional crystal structural anisotropy arrangement of functional units

Organic Brønsted Acid-Catalyzed Stereoselective Cationic RAFT Polymerization:The Effect of RAFT Agents

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Chinese Journal of Polymer Science 2024年第6期42卷 711-717页

作者： Zheng-Yi Zhang Zan yang yun Liao Sai-Hu Liao Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108China State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Beijing National Laboratory for Molecular Sciences Beijing100190China

The tacticity of vinyl polymers is a key factor affecting the properties of ***,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products ***,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of *** this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the *** extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.

关键词： Bronsted acid catalysis Stereoselective cationic polymerization RAFT polymerization Chain transfer agents Tacticity

Prediction of dissolved gas content in transformer oil based on multi-information fusion

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High Voltage 2024年第3期9卷 685-699页

作者： Tongliang yang yun Fang Chengming Zhang Chao Tang Dong Hu College of Engineering and Technology Southwest UniversityChongqingChina International R&D Center for New Technologies of Smart Grid and Equipment Southwest UniversityChongqingChina

In order to accurately predict the content and variation trend of dissolved gas in trans-former oil and guide the condition maintenance of power transformers,a combined prediction model based on multi-information fusion is proposed and its effectiveness is *** of all,based on the possibility of pathological and missing historical sample data,a detection and filling method based on variable weight combination samples is ***,the authors propose two *** at the non-linear and non-stationary characteristics of gas content,a univariate decomposition prediction mode HBA-VMD-TCN which based on the Honey Badger algorithm,variational mode decomposition and time convolutional network(TCN)is *** the multi-variate Informer prediction model is established for gas content affected by multiple ***,the cross-entropy theory is used to determine the weight coefficients of the two models,and the multi-information fusion combined prediction model is ***,on the basis of the above,a method to determine the time step and the position information of the transition point adaptively in the process of prediction is proposed to further improve the prediction *** results show that,through a series of simulation experiments of model comparison and transformer anomaly prediction,the accuracy and effectiveness of the combined prediction model are verified.

关键词： content prediction dissolved

A 2. GHz,simple 2.bit 1×8 phased array

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Journal of Electronic Science and Technology 2024年第3期22卷 26-34页

作者： Jun-Xian Liu yun-Ying Man Hao yang Peng yang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This study demonstrates a simple 2.bit phased array operating at 2. GHz that supports one-dimensional beam scanning with left-handed circular polarization(LHCP).The antenna is constructed using a compact four-layer printed circuit board(PCB)structure,consisting of a 90°phase shifter layer with microstrip structures,a ground(GND)layer,a direct current(DC)control layer,and a circularly polarized annular radiation patch layer with 1-bit phase *** on the proposed unit structure,a 1×8 array with half-wavelength inter-element spacing was designed and *** results show that the array achieves a peak gain of 10.2. dBi and is capable of beam scanning within±50°.

关键词： 2. GHz 2.bit P-i-n diodes Phased array Reconfigurable antennas

Phase Patterning of Poly(oxime-ester)for Information Encryption by Photo-induced Isomerization

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Chinese Journal of Polymer Science 2024年第10期42卷 1488-1494,I0010页

作者： Yu-Fan yang yun Bai Yi-Bao Li Chang-Fei He School of Chemistry and Chemical Engineering Gannan Normal UniversityGanzhou341000China

Crystal polymers or liquid crystal elastomers undergo a phase transition that results in a change in the corresponding optical properties,which has the potential to be applied in areas such as information encryption and *** utilization of these materials for patterning purposes requires different phase transition ***,once prepared,altering the phase transition temperature of them presents significant ***,a poly(oxime-ester)(POE)network is developed to achieve high-resolution and multilevel patterning by photo-induced *** as-prepared POE exhibits the ability to transition from an opaque state to a transparent state under temperature stimuli,with the transition temperature and kinetics dependent on UV light exposure ***,complex patterns and information can be encrypted through different selective regional exposure time and decrypted under specific temperature or cooling ***,we illustrate an example of temporal communication,where cooling time or temperature serves as the encoded *** research expands the application scope of advanced encryption materials,showcasing the potential of POE in dynamic information encryption and decryption processes.

关键词： Poly(oxime-ester) Isomerization Phase patterning Information encryption

CTSN: Predicting cloth deformation for skeleton-based characters with a two-stream skinning network

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Computational Visual Media 2024年第3期10卷 471-485页

作者： Yudi Li Min Tang yun yang Ruofeng Tong Shuangcai yang Yao Li Bailin An Qilong Kou College of Computer Science and Technology Zhejiang UniversityHangzhou 310058China Aurora Studios TencentShenzhen 518057China

We present a novel learning method using a two-stream network to predict cloth deformation for skeleton-based *** characters processed in our approach are not limited to humans,and can be other targets with skeleton-based representations such asfish or *** use a novel network architecture which consists of skeleton-based and mesh-based residual networks to learn the coarse features and wrinkle features forming the overall residual from the template cloth *** network may be used to predict the deformation for loose or tight-fitting *** memory footprint of our network is low,thereby resulting in reduced computational *** practice,a prediction for a single cloth mesh for a skeleton-based character takes about 7 ms on an nVidia GeForce RTX 3090 *** to prior methods,our network can generate finer deformation results with details and wrinkles.

关键词： cloth deformation learning network skinning

Impact of oxaliplatin and trastuzumab combination therapy on tumor markers and T lymphocyte subsets for advanced gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第9期16卷 3905-3912页

作者： Cheng-Wan Zheng yun-Mo yang Hui yang Department of Thyroid Surgery The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina

BACKGROUND Advanced gastric cancer(AGC)remains a challenging malignancy with poor *** combination of oxaliplatin and trastuzumab has shown promising results in AGC *** study aimed to investigate the effects of oxaliplatin and trastuzumab combination therapy on serum tumor markers and T lymphocyte subsets in patients with AGC and to explore their potential as predictive biomarkers for treatment *** To investigate the impact of oxaliplatin and trastuzumab combination therapy on serum markers and T cell subsets in patients with *** This prospective study enrolled 60 patients with *** patients received oxaliplatin(130 mg/m^(2.,every 3 weeks)and trastuzumab(8 mg/kg loading dose,followed by 6 mg/kg every 3 weeks)for six *** carcinoembryonic antigen(CEA),cancer antigen 19-9(CA19-9),and cancer antigen 72.4(CA72.4)were measured before and after treatment.T-lymphocyte subsets,including CD3+,CD4+,CD8+,and CD4+/CD8+ratios,were also *** clinical response was assessed using the Response Evaluation Criteria in Solid Tumors version *** After six cycles of treatment,the CEA,CA19-9,and CA72.4 serum levels significantly decreased compared to baseline levels(P<0.001).The percentages of CD3+and CD4+T lymphocytes increased significantly(P<0.05),whereas the percentage of CD8+T lymphocytes decreased(P<0.05).The CD4+/CD8+ratio also significantly increased after treatment(P<0.05).Patients with a higher decrease in serum tumor markers(≥50%reduction)and a higher increase in CD4+/CD8+ratio(≥1.5-fold)showed better clinical response rates(P<0.05).CONCLUSION Oxaliplatin and trastuzumab combination therapy effectively reduced serum tumor marker levels and modulated T lymphocyte subsets in patients with *** therapy not only has a direct antitumor effect,but also enhances the immune response in patients with *** tumor markers and T lymphocyte subsets may serve as potential predictive biomarkers for treatment respon

关键词： Advanced gastric cancer Oxaliplatin Trastuzumab Serum tumor markers T lymphocyte subsets Predictive biomarkers

Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect

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Journal of Mountain Science 2024年第3期21卷 1058-1074页

作者： CHENG yun SONG Zhanping XU Zhiwei yang Tengtian TIAN Xiaoxu School of Civil Engineering Yancheng Institute of TechnologyYancheng 224051China School of Civil Engineering Xi'an University of Architecture and TechnologyXi'an 710055China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering Xi'an 710055China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-2..50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass.

关键词： Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism Dissimilation