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Engineering Rubisco to enhance CO_(2) utilization

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Synthetic and Systems Biotechnology 2024年第1期9卷 55-68页

作者： Lei Zhao Zhen Cai yin Li Yanping Zhang CAS Key Laboratory of Microbial Physiological and Metabolic Engineering State Key Laboratory of Microbial ResourcesInstitute of MicrobiologyChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Seeds Research Syngenta Biotechnology ChinaZhong Guan Cun Life Science ParkBeijingChina

Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrogen ***,the significantly low carboxylation activity and competing oxygenase activity of Rubisco greatly impede high carbon fixation *** review first summarizes the current efforts in directly or indirectly modifying plant Rubisco,which has been challenging due to its high conservation and limitations in chloroplast transformation ***,recent advancements in understanding Rubisco biogenesis with the assistance of chaperones have enabled successful heterologous expression of all Rubisco forms,including plant Rubisco,in *** breakthrough facilitates the acquisition and evaluation of modified proteins,streamlining the measurement of their ***,the establishment of a screening system in *** opens up possibilities for obtaining high-performance mutant enzymes through directed ***,this review emphasizes the utilization of Rubisco in microorganisms,not only expanding their carbon-fixing capabilities but also holding significant potential for enhancing biotransformation processes.

关键词： Rubisco Plant CO_(2)fixation Microbial Carbon fixation pathway Synthetic biology Enzyme engineering

Autonomous navigation of an asteroid orbiter enhanced by a beacon satellite in a high-altitude orbit

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Astrodynamics 2024年第3期8卷 375-400页

作者： Weidong yin Yu Shi Leizheng Shu Yang Gao University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing100094China

This study aims to assess the autonomous navigation performance of an asteroid orbiter enhanced using an inter-satellite link to a beacon *** navigation includes the orbit determination of the orbiter and beacon,and asteroid gravity estimation without any ground station *** measurements were acquired using satellite-to-satellite tracking(SST)and optical observation of asteroid surface *** study presents a new orbiter-beacon SST scheme,in which the orbiter circumnavigates the asteroid in a low-altitude strongly-perturbed orbit,and the beacon remains in a high-altitude weakly-perturbed *** used Asteroid 433 Eros as an example,and analyzed and designed low-and high-altitude orbits for the orbiter and *** navigation measurements were precisely modeled,extended Kalman filters were devised,and observation configuration was analyzed using the Cramer-Rao lower bound(CRLB).Monte Carlo simulations were carried out to assess the effects of the orbital inclination and altitudes of the orbiter and beacon as key influencing *** simulation results showed that the proposed SST scheme was an effective solution for enhancing the autonomous navigation performance of the orbiter,particularly for improving the accuracy of gravity estimation.

关键词： asteroid exploration gravity estimation orbit determination satellite-to-satellite tracking(SST) optical observation

Rapid chemical recycling of waste polyester plastics catalyzed by recyclable catalyst

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Green Chemical Engineering 2024年第2期5卷 257-265页

作者： Yu-Ji Luo Jia-yin Sun Zhi Li School of Physical Science and Technology ShanghaiTech UniversityShanghai201210China

Waste plastics are serious environmental threats due to their low degradability and low recycling *** and efficient waste plastics recycling technologies are urgently demanded for a sustainable ***,we report a rapid,closed-loop,and streamlined process to convert polyesters such as poly(ethylene terephthalate)(PET)back to its purified *** trifluoromethanesulfonic acid or metal triflates as the recyclable catalyst,polyesters such as PET can be completely depolymerized by simple carboxylic acids within 1 *** coupling this acidolysis with a subsequent hydrogenolysis process,the consumed carboxylic acid was recovered and the closed-loop of PET depolymerization could be *** catalysts and depolymerization agents are fully recycled while only PET and hydrogen are consumed.

关键词： Chemical recycling Waste polyester plastics Acidolysis Recyclable catalyst

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Study on detecting main ingredients of silicone rubber based on terahertz spectrum

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High Voltage 2024年第3期9卷 518-527页

作者： Hongwei Mei Lanxin Li Fanghui yin Liming Wang Masoud Farzaneh Shenzhen International Graduate School(SIGS) Tsinghua UniversityShenzhenGuangdongChina Kunming Power Exchange Center KunmingYunnanChina Department of Applied Sciences(DSA) University of Quebec at ChicoutimiChicoutimiQuebecCanada

The authors investigated the ingredient detection technique of silicone rubber based on the Terahertz *** this purpose,18 diverse high-temperature vulcanised silicone rubber(HTVSR)formulations were customised,8 of which are used as calibration set while the rest 10 as prediction *** on the Beer-Lambert Law,the partial-least-square(PLS)regression model and the least-squares support-vector machines(LS-SVM)regression model were used to yield the relationships between the absorption spectrums and the content percentages of polydimethylsiloxane(PDMS),alumina tri-hydrate(ATH),and silica in *** results showed that for the formulations tested,the prediction accuracy of all three main ingredients by the PLS regression model could be improved by changing the spectrum range from 0.2–4 to 0.5–2 *** the data were pre-processed by the Savitzky–Golay smoothing method or multiplicative scatter correction method,the prediction accuracy of PDMS could be further ***,this would lead to a slight decrease in the prediction accuracy of *** the LS-SVM regression model,the radial basis function(RBF)kernel and the linear kernel were *** was found that the prediction accuracy of both kernels was better than that of the PLS regression *** the LS-SVM regression model using the RBF kernel,the correlated coefficients of PDMS and ATH in the prediction set could be up to 0.9915 and 0.9742,respectively.

关键词： rubber spectrum kernel

Global output feedback regulation of time-varying nonlinear systems via the dual-gain method

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Science China(Information Sciences) 2024年第5期67卷 333-334页

作者： Xian-Long yin Zong-Yao SUN Changyun WEN Institute of Automation Qufu Normal University School of Electrical and Electronic Engineering Nanyang Technological University

Notably, owing to the limited information available, the problem of output feedback stabilization/regulation for nonlinear systems has been explored based on state *** addition, the sensors accounting for state measurement could fail to detect the system states accurately due to the limitations of manufacturing techniques and instruments.

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Preparation and performance improvement of a dual-component microcapsule self-healing system for silicone rubber insulating material

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High Voltage 2024年第2期9卷 453-465页

作者： Mingzhe Li Bin Cao Fanghui yin Hongwei Mei Liming Wang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating *** establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service *** this study,poly(urea-formaldehyde)microcapsules containing polydimethylsiloxane healing agents are prepared and a dual-component microcapsule self-healing system for silicone rubber material is established and *** addition,the key factors affecting the self-healing performance(such as microcapsule size,rupture rate,and microcapsule doping amount)are *** is found that when SYLGARDTM 184 is used as the healing agent and matrix,with a 4:6(A:B)doping ratio of dual-component microcapsules and 20 phr doping amount,the self-healing efficiency is approximately 51%.Furthermore,increasing the microcapsule rupture rate and the interface strength between the healing agent and the matrix can effectively improve the self-healing *** relationships between key factors and self-healing performance are theoretically *** on the relationships,the microcapsule self-healing system can be appropriately *** results of this paper can provide a reference for the development of long-life silicone rubber insulating materials.

关键词： service rubber performance

SWG: an architecture for sparse weight gradient computation

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Science China(Information Sciences) 2024年第2期67卷 302-321页

作者： Weiwei WU Fengbin TU Xiangyu LI Shaojun WEI Shouyi yin School of Integrated Circuits Tsinghua University Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology

On-device training for deep neural networks(DNN) has become a trend due to various user preferences and scenarios. The DNN training process consists of three phases, feedforward(FF), backpropagation(BP), and weight gradient(WG) update. WG takes about one-third of the computation in the whole training process. Current training accelerators usually ignore the special computation property of WG and process it in a way similar to FF/BP. Besides, the extensive data sparsity existing in WG, which brings opportunities to save computation, is not well explored. Nevertheless, exploiting the optimization opportunities would meet three underutilization problems, which are caused by(1) the mismatch between WG data dimensions and hardware parallelism,(2) the full sparsity, i.e., the sparsity of feature map(Fmap),error map(Emap), and gradient, and(3) the workload imbalance resulting from irregular sparsity. In this paper, we propose a specific architecture for sparse weight gradient(SWG) computation. The architecture is designed based on hierarchical unrolling and sparsity-aware(HUSA) dataflow to exploit the optimization opportunities of the special computation property and full data sparsity. In HUSA dataflow, the data dimensions are unrolled hierarchically on the hardware architecture. A valid-data trace(VDT) mechanism is embedded in the dataflow to avoid the underutilization caused by the two-sided input sparsity. The gradient is unrolled in PE to alleviate the underutilization induced by output sparsity while maintaining the data reuse opportunities. Besides, we design an intra-and inter-column balancer(IIBLC) to dynamically tackle the workload imbalance problem resulting from the irregular sparsity. Experimental results show that with HUSA dataflow exploiting the full sparsity, SWG achieves a speedup of 12.23× over state-of-the-art gradient computation architecture, Train Ware. SWG helps to improve the energy efficiency of the state-of-the-art training accelerator LNPU from

关键词： CNN training gradient computation sparsity architecture

Bifunctional interstitial phosphorous doping strategy boosts platinum-zinc alloy for efficient ammonia oxidation reaction and hydrogen evolution reaction

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Nano Research 2024年第3期17卷 1182-1189页

作者： Tianqi Yu Kexin Tan Jia Wu Yongjin Zou Shibin yin Guangxi Key Laboratory of Electrochemical Energy Materials School of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Information Materials Guilin University of Electronic TechnologyGuilin 541004China

It is still a lack of bifunctional catalysts for ammonia oxidation reaction(AOR)and hydrogen evolution reaction(HER)due to their different reaction *** this work,P is doped into PtZn alloy by calcination with NaH_(2)PO_(2) as P source to induce the lattice tensile strain of Pt and the electronic interaction between P and Zn,which optimizes the AOR and HER activity *** sample with the optimal P content can drive the AOR peak current density of 293.6 mA·mgPt^(-1),which is almost 2.7 times of *** HER,the overpotential at^(-1)0 mA·cm^(-2) is only 23 mV with Tafel slope of 34.1 mV·dec^(-1).Furthermore,only 0.59 V is needed to obtain 50 mA·mgPt^(-1) for ammonia electrolysis under a two-electrode ***,this work shows an ingenious method to design bifunctional catalysts for ammonia electrolysis.

关键词： PtZn alloy phosphorous doping ammonia oxidation reaction hydrogen evolution reaction bifunctional catalyst

Neurotoxicity of tetramethylammonium ion on larval and juvenile zebrafish:Effects on neurobehaviors and multiple biomarkers

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Journal of Environmental Sciences 2024年第9期143卷 138-147页

作者： Ruixin Zhang Rui Wang Jiajun Chang GDaniel Sheng Daqiang yin Key Laboratory of Yangtze River Water Environment Ministry of EducationCollege of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Tetramethylammonium hydroxide(TMAH)is an important compound that utilized and released by the rapidly expanding semiconductor industry,which could hardly be removed by the conventional wastewater treatment *** a cholinergic agonist,the tetramethylammonium ion(TMA^(+))has been reported to induce toxicity to muscular and respiratory systems of mammals and human,however the toxicity on aquatic biota remains poorly *** investigated the neurotoxic effects of TMA^(+)exposure on zebrafish,based on neurobehavior tests and a series of *** inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L,and significant alterations on swimming path angles(straight and deflective movements)occurred even at 10 mg/*** tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species(ROS)and malondialdehyde(MDA),significantly negatively related with the activities of antioxidant enzymes,but not significantly correlated with the level of acetylcholinesterase(AChE).Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress,rather than the alterations of *** the highest exposure concentration(200 mg/L),TMA^(+)evoked more severe toxicity on zebrafish juveniles,showing significantly stronger elevation on the MDA activity,and greater inhibitions on the activities of antioxidant enzymes and ACh E,suggesting juveniles were more susceptible to TMA^(+)exposure than larval zebrafish.

关键词： Tetramethylammonium Zebrafish Oxidative stress Acetylcholinesterase Neurobehavior

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