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Uncovering the largest negative carbon isotope excursion in Earth history

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Science China Earth Sciences 2024年第3期67卷 885-889页

作者： Chao li haiyang WANG State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

The carbon cycle plays a pivotal role in regulating Earth’s surface environment through atmospheric-oceanic acid-base and redox processes, functioning as the engine driving the evolution of our planet’s surface. A deep understanding of the carbon cycle’s evolution is thus essential for our understanding of the evolution of our planet’s habitability.

关键词： carbon planet evolution

GIGANTEA orthologs,E2 members,redundantly determine photoperiodic flowering and yield in soybean

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Journal of Integrative Plant Biology 2023年第1期65卷 188-202页

作者： lingshuang Wang Haiyang Li Milan He lidong Dong Zerong Huang liyu Chen haiyang Nan Fanjiang Kong Baohui liu Xiaohui Zhao Guangdong Key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life Sciences Guangzhou UniversityGuangzhou 510006 China National Key Laboratory of Crop Genetics and Germplasm Enhancement National Center for Soybean ImprovementJiangsu Collaborative Innovation Center for Modern Crop Production Nanjing Agricultural UniversityNanjing 210095 China

Soybean(Glycine max L.)is a typical photoperiodsensitive crop,such that photoperiod determines its flowering time,maturity,grain yield,and phenological adaptability.During evolution,the soybean genome has undergone two duplication events,resulting in about 75%of all genes being represented by multiple copies,which is associated with rampant gene redundancy.Among duplicated genes,the important soybean maturity gene E2 has two homologs,E2-like a(E2La)and E2-like b(E2Lb),which encode orthologs of Arabidopsis GIGANTEA(GI).Although E2 was cloned a decade ago,we still know very little about its contribution to flowering time and even less about the function of its homologs.Here,we generated single and double mutants in E2,E2La,and E2Lb by genome editing and determined that E2 plays major roles in the regulation of flowering time and yield,with the two E2 homologs depending on E2 function.At high latitude regions,e2 single mutants showed earlier flowering and high grain yield.Remarkably,in terms of genetic relationship,genes from the legume-specific transcription factor family E1 were epistatic to E2.We established that E2 and E2-like proteins form homodimers or heterodimers to regulate the transcription of E1 family genes,with the homodimer exerting a greater function than the heterodimers.In addition,we established that the H3 haplotype of E2 is the ancestral allele and is mainly restricted to low latitude regions,from which the loss-of-function alleles of the H1 and H2haplotypes were derived.Furthermore,we demonstrated that the function of the H3 allele is stronger than that of the H1 haplotype in the regulation of flowering time,which has not been shown before.Our findings provide excellent allelic combinations for classical breeding and targeted gene disruption or editing.

关键词： E2 E2-like flowering time GIGANTEA natural variation redundancy yield

Thermal Transport through Solid-liquid Interface:Effect of the Interfacial Coupling and Nanostructured Surfaces

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Journal of Thermal Science 2022年第4期31卷 1167-1179页

作者： li haiyang WANG Jun XIA Guodong MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation Beijing Key Laboratory of Heat Transfer and Energy Conversion Beijing University of TechnologyBeijing 100124China

The solid-liquid interfacial thermal transport depends on the physical properties of the interfaces,which have been studied extensively in open literature.However,the fundamental understanding on the mechanism of the solid-liquid interfacial thermal transport is far from clear.In the present paper,heat transfer through solid-liquid interfaces is studied based on the non-equilibrium molecular dynamics simulations.It is shown that the interfacial heat transfer can be enhanced by increasing interfacial coupling strength or introducing the nanostructured surfaces.The underlying mechanism of the interfacial thermal transport is analyzed based on the calculation results of the heat flux distribution,potential mean force,and the vibrational density of states at the interfacial region.It is found that the interfacial thermal transport is dominated by the kinetic and virial contributions in the interface region.The enhancement of the interfacial heat transfer can be attributed to the fluid adsorption on the solid surface under a strong interfacial interaction or by the nanostructured solid surfaces,which reduce the mismatch of the vibrational density of states at the solid-liquid interface region.

关键词： solid-liquid interface molecular dynamics simulation thermal resistance nanostructure

Sequence optimization for multiple asteroids rendezvous via cluster analysis and probability-based beam search

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Science China(Technological Sciences) 2021年第1期64卷 122-130页

作者： li haiyang BAOYIN HeXi School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

It is of great significance to visit multiple asteroids in a space mission.In this paper,the multiple asteroids mission optimization is implemented using cluster analysis and probability-based beam search.Clustering is performed to select the first asteroid to visit.Four cluster algorithms are investigated and affinity propagation is selected.Then four beam search algorithms that are deterministic beam search and three probability-based beam search variants,probabilistic beam search,ant-colony beam search,and evolving beam search,are applied to search for the rendezvous sequence.Deterministic beam search as a heuristic tree search algorithm is widely applied in multitarget sequence optimization,but it has an obvious drawback of the conflict between the number of pruned nodes and the possibility of finding optimal solutions,which can be improved by probability-based beam search.Among three probability-based beam search,the ant-colony beam search has a learning mechanism,and evolving beam search is constructed based on ant-colony beam search and has an evolutionary mechanism.Results show that the introduction of randomness can improve beam search,and beam search variants with the learning and evolutionary mechanism have an excellent performance.

关键词： interplanetary trajectory optimization multi-target mission cluster analysis probability-based beam search

Practical Structural Design Approach of Multiconfiguration Planar Single‑Loop Metamorphic Mechanism with a Single Actuator

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Chinese Journal of Mechanical Engineering 2020年第5期33卷 19-33页

作者： Qiang Yang Guangbo Hao Shujun li Hongguang Wang Haiyang Li College of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Department of Electrical and Electronic Engineering University College CorkCork T12 K8AFIreland State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China

As a type of multiconfiguration mechanism that can operate in an under-actuated state,metamorphic mechanisms were proposed more than two decades ago and attracted significant interest.Studies on structural synthesis of metamorphic mechanisms tend to focus more on metamorphic techniques and the structural synthesis of source mechanisms for metamorphic mechanisms.By designing different constraint architectures of metamorphic joints,multistructures can be obtained from the same source metamorphic mechanism.To determine the constraint architectures of metamorphic joints and their different assembly combinations,a kinematic status matrix and a corresponding constraint status matrix are constructed based on the metamorphic cyclogram of a source mechanism.According to the equivalent resistance gradient model and the constraint status matrix,an equivalent resistance matrix for the metamorphic joints is proposed.A structural synthesis matrix of the metamorphic mechanism is then obtained from the equivalent resistance matrix by deducing the constraint form vectors of the metamorphic joints.Furthermore,a kinematic diagram synthesis of the source metamorphic mechanism of a planar single-loop metamorphic mechanism is proposed,which is based on only the 14 one-or zero-degrees-of-freedom linkage groups.The entire structural design method of a metamorphic mechanism is based on the structural synthesis matrix and is presented as a systematic process.Finally,the proposed structural design approach is illustrated by two examples to verify its feasibility and practicality.This study provides an effective method for designing a practical multi-mobility and multiconfiguration planar single-loop metamorphic mechanism with a single actuator.

关键词： Metamorphic mechanism Structural design Form of metamorphic joints Multiconfiguration Equivalent resistance Single actuator

A brief review on nonlinear modeling methods and applications of compliant mechanisms

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Frontiers of Mechanical Engineering 2016年第2期11卷 119-128页

作者： Guangbo HAO Jingjun YU Haiyang Li School of Engineering University College Cork Cork T12 YN60Ireland School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191 China

因为他们的优点，顺从的机制(厘米) 在机制和机器人学成为了最流行的研究主题之一。这篇论文试图在非线性的静态的建模途径的进展和厘米的应用上提供简短系统的评论为联系理论和另外的新应用支持学科交差 / 多学科的开发。它也预言应用... 详细信息

因为他们的优点，顺从的机制(厘米) 在机制和机器人学成为了最流行的研究主题之一。这篇论文试图在非线性的静态的建模途径的进展和厘米的应用上提供简短系统的评论为联系理论和另外的新应用支持学科交差 / 多学科的开发。它也预言应用和理论开发的可能的未来方向。

关键词：建模方法非线性应用柔顺机构综述兼容机制机器人 CMS

Tunable Thermal Rectification and Negative Differential Thermal Resistance in Gas-Filled Nanostructure with Mechanically-Controllable Nanopillars

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Journal of Thermal Science 2022年第4期31卷 1084-1093页

作者： li Fan li haiyang WANG Jun XIA Guodong HWANG Gisuk MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation Beijing Key Laboratory of Heat Transfer and Energy ConversionBeijing University of TechnologyBeijing 100124China Department of Mechanical Engineering Wichita State University Wichita KS 67260USA

In this study,by using the nonequilibrium molecular dynamics and the kinetic theory,we examine the tailored nanoscale thermal transport via a gas-filled nanogap structure with mechanically-controllable nanopillars in one surface only,i.e.,changing nanopillar height.It is found that both the thermal rectification and negative differential thermal resistance(NDTR)effects can be substantially enhanced by controlling the nanopillar height.The maximum thermal rectification ratio can reach 340%and the△T range with NDTR can be significantly enlarged,which can be attributed to the tailored asymmetric thermal resistance via controlled adsorption in height-changing nanopillars,especially at a large temperature difference.These tunable thermal rectification and NDTR mechanisms provide insights for the design of thermal management systems.

关键词： thermal rectification negative differential thermal resistance kinetic theory nanopillars

Breath-by-breath measurement of exhaled ammonia by acetonemodifier positive photoionization ion mobility spectrometry via online dilution and purging sampling

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Journal of Pharmaceutical Analysis 2023年第4期13卷 412-420页

作者： Lu Wang Dandan Jiang Lei Hua Chuang Chen Dongming li Weiguo Wang Yiqian Xu Qimu Yang Haiyang Li Song Leng CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Health Management Center The Second Affiliated Hospital of Dalian Medical UniversityDalian116023China University of Chinese Academy of Sciences Beijing100049China Dalian Key Laboratory for Online Analytical Instrumentation Dalian116023China Dalian Engineering Research Center of Breath Diagnostic Technology Dalian116023China

Exhaled ammonia(NH_(3))is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualitative and quantitative analysis of exhaled NH_(3)with high selectivity and sensitivity.Acetone was introduced into the drift tube along with the drift gas as a modifier,and the characteristic NH_(3)product ion peak of(C_(3)H_(6)O)_(4)NH_(4)^(+)(K_(0)=1.45 cm^(2)/V·s)was obtained through the ion-molecule reaction with acetone reactant ions(C_(3)H_(6)O)_(2)H^(+)(K_(0)=1.87 cm^(2)/V·s),which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH_(3)qualitative identification.Moreover,the interference of high humidity and the memory effect of NH_(3)molecules were significantly reduced via online dilution and purging sampling,thus realizing breath-by-breath measurement.As a result,a wide quantitative range of 5.87-140.92μmol/L with a response time of 40 ms was achieved,and the exhaled NH_(3)profile could be synchronized with the concentration curve of exhaled CO_(2).Finally,the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH_(3)of healthy subjects,demonstrating its great potential for clinical disease diagnosis.

关键词： Photoionization ion mobility spectrometry Acetone modifier Exhaled ammonia Breath analysis

Evaluating data-driven algorithms for predicting mechanical properties with small datasets:A case study on gear steel hardenability

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 836-847页

作者： Bogdan Nenchev Qing Tao Zihui Dong Chinnapat Panwisawas Haiyang Li Biao Tao Hongbiao Dong NISCO UK Research Centre School of EngineeringUniversity of LeicesterLeicester LE17RHUK Nanjing Iron&Steel United Co. Ltd.Nanjing 210044China

Data-driven algorithms for predicting mechanical properties with small datasets are evaluated in a case study on gear steel hardenability.The limitations of current data-driven algorithms and empirical models are identified.Challenges in analysing small datasets are discussed,and solution is proposed to handle small datasets with multiple variables.Gaussian methods in combination with novel predictive algorithms are utilized to overcome the challenges in analysing gear steel hardenability data and to gain insight into alloying elements interaction and structure homogeneity.The gained fundamental knowledge integrated with machine learning is shown to be superior to the empirical equations in predicting hardenability.Metallurgical-property relationships between chemistry,sample size,and hardness are predicted via two optimized machine learning algorithms:neural networks(NNs)and extreme gradient boosting(XGboost).A comparison is drawn between all algorithms,evaluating their performance based on small data sets.The results reveal that XGboost has the highest potential for predicting hardenability using small datasets with class imbalance and large inhomogeneity issues.

关键词： machine learning small dataset XGboost hardenability gear steel