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Building Simulation 2023年第11期16卷 2159-2176页

作者： xianzhong chen Rang Tu Ming Li Xu Yang Kun Jia School of Civil and Resources Engineering University of Science and Technology BeijingBeijing100083China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China China Electronics Engineering Design Institute CO. LTD.Beijing100142China

In this paper,models to predict hot spot temperature and to estimate cooling air’s working parameters of racks in data centers were established using machine learning algorithms based on simulation ***,simulation models of typical racks were established in computational fluid dynamics(CFD).The model was validated with field test results and results in literature,error of which was less than 3%.Then,the CFD model was used to simulate thermal environments of a typical rack considering different factors,such as servers’power,which is from 3.3 kW to 20.1 kW,cooling air’s inlet velocity,which is from 1.0 m/s to 3.0 m/s,and cooling air’s inlet temperature,which is from 16℃ to 26℃ The highest temperature in the rack,also called hot spot temperature,was selected for each ***,a prediction model of hot spot temperature was built using machine learning algorithms,with servers’power,cooling air’s inlet velocity and cooling air’s inlet temperature as inputs,and the hot spot temperatures as ***,based on the prediction model,an operating parameters estimation model was established to recommend cooling air’s inlet temperatures and velocities,which can not only keep the hot spot temperature at the safety value,but are also energy saving.

关键词： data center CFD simulation hot spot temperature machine learning algorithm prediction and estimation models

Reconstruction of tyrosol synthetic pathways in Escherichia coli

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2615-2621页

作者： Cui Yang xianzhong chen Junzhuang Chang Lihua Zhang Wei Xu Wei Shen You Fan Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education Jiangnan University School of Biotechnology Jiangnan University

Tyrosol is a pharmacologically active phenolic compound widely used in the medicine and chemical *** methods of plant extraction are complicated and chemical synthesis of tyrosol is not commercially viable. In this study, a recombinant Escherichia coli strain was constructed by overexpressing the phenylpyruvate decarboxylase ARO10 from Saccharomyces cerevisiae, which could produce tyrosol from glucose. Furthermore,genes encoding key enzymes from the competing phenylalanine and tyrosine synthesis pathways and the repression protein TyrR were eliminated, and the resulting engineered strain generated 3.57 mmol·L^(-1) tyrosol from glucose. More significantly, codon optimization of ARO10 increased expression and tyrosol titer. Using the novel engineered strain expressing codon-optimized AR10 in shake-flask culture, 8.72 mmol·L^(-1) tyrosol was obtained after 48 h. Optimization of the induction conditions improved tyrosol production to 9.53 mmol·L^(-1)(1316.3 mg·L^(-1)). A higher titer of tyrosol was achieved by reconstruction of tyrosol synthetic pathway in E. coli.

关键词： Tyrosol Escherichia coli Phenylpyruvate decarboxylase Gene knockout Codon optimization

Color-selective three-dimensional polarization structures

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Light(Science & Applications) 2022年第11期11卷 2706-2715页

作者： Yuttana Intaravanne Ruoxing Wang Hammad Ahmed Yang Ming Yaqin Zheng Zhang-Kai Zhou Zhancheng Li Shuqi chen Shuang Zhang xianzhong chen Institute of Photonics and Quantum Sciences School of Engineering and Physical SciencesHeriot-Watt UniversityEdinburgh EH144ASUK Department of Mathematics and Physics North China Electric Power UniversityBaoding 071003China School of Physics and Electronic Engineering Changshu Institute of TechnologySuzhou 215000China State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China School of Physics and TEDA Applied Physics Institute Nankai University94 Weijin RoadTianjin 300071China Department of Physics University of Hong KongHong KongChina Department of Electronic&Electrical Engineering University of Hong KongHong KongChina

Polarization as an important degree of freedom for light plays a key role in *** beams with controlled polarization profles have diverse applications,such as information encoding,display,medical and biological imaging,and manipulation of ***,conventional polarization optics can only realize two-dimensional polarization structures in a transverse *** emergent ultrathin optical devices consisting of planar nanostructures,so-called metasurfaces,have shown much promise for polarization *** we propose and experimentally demonstrate color-selective three-dimensional(3D)polarization structures with a single *** geometric metasurfaces are designed based on color and phase multiplexing and polarization rotation,creating various 3D polarization ***,different 3D polarization knots in the same observation region can be achieved by controlling the incident wavelengths,providing unprecedented polarization control with color information in 3D *** research findings may be of interest to many practical applications such as vector beam generation,virtual reality,volumetric displays,security,and anti-counterfeiting.

关键词： polarization optics dimensional

Multifaceted control of focal points along an arbitrary 3D curved trajectory

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Light(Science & Applications) 2024年第10期13卷 2376-2388页

作者： Muhammad Afnan Ansari Hammad Ahmed Yan Li Guanchao Wang Jemma E.Callaghan Ruoxing Wang James Downing xianzhong chen Institute of Photonics and Quantum Sciences School of Engineering and Physical SciencesHeriot-Watt UniversityEdinburgh EH144ASUK School of Materials Zhengzhou University of AeronauticsZhengzhou 450015China School of Physics Harbin Institute of TechnologyHarbin 150001China STMicroelectronics 1TanfieldInverleith RowEdinburgh EH35DAUK Department of Mathematics and Physics North China Electric Power UniversityBaoding 071003China

Metalenses can integrate the functionalities of multiple optical components thanks to the unprecedented capability of optical metasurfaces in light *** the rapid development of optical metasurfaces,metalenses continue to *** and color play a very important role in understanding optics and serve as valuable tools for gaining insights into our *** from the design flexibility of metasurfaces,we propose and experimentally demonstrate a super metalens that can realize multifaceted control of focal points along any 3D curved *** wavelengths and polarization states of all focal points are engineered in a desirable *** super metalens can simultaneously realize customized 3D positioning,polarization states,and wavelengths of focal points,which are experimentally demonstrated with incident wavelengths ranging from 501 to 700 *** further showcase the application of the developed super metalenses in 3D optical distance *** compact nature of metasurfaces and unique properties of the proposed super metalenses hold promise to dramatically miniaturize and simplify the optical architecture for applications in optical metrology,imaging,detection,and security.

关键词： polarization curved facet

Helicity dependent directional surface plasmon polariton excitation using a metasurface with interfacial phase discontinuity

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Light(Science & Applications) 2013年第1期2卷 197-203页

作者： Lingling Huang xianzhong chen Benfeng Bai Qiaofeng Tan Guofan Jin Thomas Zentgraf Shuang Zhang School of Physics&Astronomy University of BirminghamBirmingham B152TTUK State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084China Department of Physics University of PaderbornD-33098 PaderbornGermany

Surface plasmon polaritons(SPPs)have been widely exploited in various scientific communities,ranging from physics,chemistry to biology,due to the strong confinement of light to the metal *** many applications,it is important that the free space photon can be coupled to SPPs in a controllable *** this Letter,we apply the concept of interfacial phase discontinuity for circularly polarizations on a metasurface to the design of a novel type of polarization-dependent SPP unidirectional excitation at normal *** unidirectional excitation of SPPs along opposite directions is experimentally demonstrated at optical frequencies by simply switching the helicity of the incident *** approach,in conjunction with dynamic polarization modulation techniques,opens gateway towards integrated plasmonic circuits with electrically reconfigurable functionalities.

关键词： metamaterials metasurface surface plasmon

High-resolution grayscale image hidden in a laser beam

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Light(Science & Applications) 2017年第1期6卷 243-248页

作者： Fuyong Yue Chunmei Zhang Xiao-Fei Zang Dandan Wen Brian D Gerardot Shuang Zhang xianzhong chen SUPA Institute of Photonics and Quantum SciencesSchool of Engineering and Physical SciencesHeriot-Watt UniversityEdinburgh EH144ASUK Shanghai Key Lab of Modern Optical System University of Shanghai for Science and TechnologyShanghai 200093China School of Physics and Astronomy University of BirminghamBirmingham B152TTUK

Images perceived by human eyes or recorded by cameras are usually optical patterns with spatially varying intensity or color *** addition to the intensity and color,the information of an image can be encoded in a spatially varying distribution of phase or polarization ***,such images might not be able to be directly viewed by human eyes or cameras because they may exhibit highly uniform intensity ***,we propose and experimentally demonstrate an approach to hide a high-resolution grayscale image in a square laser beam with a size of less than half a *** image with a pixel size of 300×300 nm is encoded into the spatially variant polarization states of the laser beam,which can be revealed after passing through a linear *** unique technology for hiding grayscale images and polarization manipulation provides new opportunities for various applications,including encryption,imaging,optical communications,quantum science and fundamental physics.

关键词： grayscale image metasurface polarization manipulation

RGB Color Decomposition and Image Feature Extraction of Flame Image in Rear of Sintering Machine 36

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RGB Color Decomposition and Image Feature Extraction of Flam...

Compact multi-foci metalens spectrometer

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作者： Wu chen Wang Fubin chen xianzhong Hou Qingwen chen Zhikun Zhang Meng Yang Haolong School of Automation Engineering University of Science & Technology Beijing School of Electrical Engineering North China University of Science and Technology

ISBN: (纸本)9781538629185

The stability of the sintering end point is an important precondition for the smooth running of the sintering machine and the assurance of the quality and quantity of sintering *** sintering flame of the sintering machine tail involves a great deal of associated information about sintering end *** the image feature of the flame has important significance forjudging the operation state of ***,taking flame image of normal sintering as research objects,analyzing the energy information in the flame image;Secondly,reducing the halo effect on the image by processing image with Discrete Fourier transform（DFT）;Thirdly,using the color decomposition method to decompose the RGB image into three components of R,G and B,obtaining the principal component image of RGB by removing the background of image;Finally,obtaining ideal binary image through threshold segmentation and mathematical morphology processing on image,and realizing geometric features extraction of the flame image.

关键词： Sintering machine Flame image Color decomposition Image segmentation Feature extraction

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Light(Science & Applications) 2023年第5期12卷 905-914页

作者： Ruoxing Wang Muhammad Afnan Ansari Hammad Ahmed Yan Li Wenfeng Cai Yanjun Liu Songtao Li Jianlong Liu Li Li xianzhong chen Department of Mathematics and Physics North China Electric Power University071003 BaodingChina Institute of Photonics and Quantum Sciences School of Engineering and Physical SciencesHeriot-Watt UniversityEdinburgh EH144ASUK School of Materials Zhengzhou University of Aeronautics450015 ZhengzhouChina Department of Electrical and Electronic Engineering Southern University of Science and Technology518055 ShenzhenChina College of Physics and Optoelectronic Engineering Harbin Engineering University150001 HarbinChina School of Physics Harbin Institute of Technology150001 HarbinChina

A lightweight and portable spectrometer is desirable for miniaturization and *** unprecedented capability of optical metasurfaces has shown much promise to perform such a *** propose and experimentally demonstrate a compact high-resolution spectrometer with a multi-foci *** novel metalens is designed based on wavelength and phase multiplexing,which can accurately map the wavelength information into its focal points located on the same *** measured wavelengths in the light spectra agree with simulation results upon the illumination of various incident light *** uniqueness of this technique lies in the novel metalens that can simultaneously realize wavelength splitting and light *** compactness and ultrathin nature of the metalens spectrometer render this technology have potential applications in on-chip integrated photonics where spectral analysis and information processing can be performed in a compact platform.

关键词： spectra uniqueness illumination

Enhancing thermostability and activity of sucrose phosphorylase for high-level production of 2-O-α-d-glucosylglycerol

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Systems Microbiology and Biomanufacturing 2022年第4期2卷 643-652页

作者： Linli Yang Lukasz Peplowski Yujuan Shen Haiquan Yang xianzhong chen Wei Shen Yuanyuan Xia Key Laboratory of Industrial Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan University1800 Lihu AvenueWuxi 214122JiangsuChina Institute of Physics Faculty of PhysicsAstronomy and InformaticsNicolaus Copernicus University in TorunGrudziadzka 587-100 TorunPoland

Sucrose phosphorylase(SPase)can transfer the glucosyl group of sucrose to different compounds and has been widely used in *** overcome the low thermostability of the sucrose phosphorylase from Leuconostoc mesenteroides ATCC 12291(LmSP),a method named PROSS was used to construct mutants with increased *** variants were screened by measuring their residual activities after heating at 50℃.Then,a single point mutant and a combined mutant with improved thermostability and activity were *** half-lives of mutants at 50℃ were approximately twice as high as those of the wild *** addition,2-O-α-d-glucosylglycerol(αGG)was synthesized by the wild type and the two improved variants,and the reaction conditions were *** the conditions of glycerol concentration of 3.2 mol/L,sucrose concentration of 1.2 mol/L,and enzyme concentration of 40 U/mL at 37℃ for 60 h,the yield ofαGG reached the maximum,and the sucrose conversion rate of the wild type,the mutant V23L and the combined mutant V23L/S424R were 62.3%,70.7%and 76.3%,*** this study,SPase mutants with higher activity and stability were obtained,and achieved high-level production ofαGG.

关键词： Sucrose phosphorylase PROSS Thermostability 2-O-α-d-Glucosylglycerol

Development of surface displaying system for heterologous protein expression in Candida tropicalis

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Systems Microbiology and Biomanufacturing 2023年第2期3卷 298-311页

作者： Tingting Wang Haibing Zhang Mengxuan Li Jiaxi Zheng Yuanyuan Xia Haiquan Yang Wei Shen xianzhong chen Key Laboratory of Industrial Biotechnology Ministry of EducationJiangnan UniversityWuxi 214122China School of Biotechnology Jiangnan UniversityWuxiChina

The purpose of this study was to assess the potential application of cell surface display in Candida *** display gene cassettes were constructed using five anchoring proteins from Saccharomyces cerevisiae,three of which[(suppression of exponential defect protein,SED1),(cell wall protein 2,CWP2)and(delayed anaerobic protein 4,DAN4)]were reported to show higher activity of heterologous proteins thanα-agglutinin(AGα1).The performance of yeast-enhanced green fluorescent protein(yeGFP)was evaluated using laser scanning confocal microscopy and flow *** results showed that the three anchoring regions(SED1,CWP2 and AGα1)successfully displayed yeGFP on the cell *** investigate the effect of the three anchoring proteins on the surface display of Rhizopus oryzaeα-amylase(ROA1)and Aspergillus aculeatusβ-glucosidase(BGL1)in ***,we constructed surface display gene cassettes for ROA1 and BGL1,*** strains containing the anchoring proteins SED1 and CWP2 showed higher activity of ROA1 and BGL1 than the strains containing the anchoring protein AGα*** highest ROA1 and BGL1 activities of strains with SED1 were 6.37 U/g CDW and 7.93 U/g CDW,respectively,which were sixfold and eightfold higher than those of strain with AGα*** addition,we also optimized signal *** results indicated that signal peptides have an impact on enzyme activity.

关键词： Yeast surface display Anchoring protein Glycosylphosphatidylinositol(GPI) α-Amylase β-Glucosidase Whole cell catalysis