New approach for detecting a compressed bino/wino at the LHC

Han, Chengcheng,Wu, Lei,Yang, Jin Min,Zhang, Mengchao,Zhang, Yang American Physical Society 2015 PHYSICAL REVIEW D - Vol.91 No.5

Physiological responses and small RNAs changes in maize under nitrogen deficiency and resupply

Zhenchao Yang,Zhengyan Wang,Chengcheng Yang,Zhao Yang,Hongquan Li,Yongjun Wu 한국유전학회 2019 Genes & Genomics Vol.41 No.10

Background Maize is an important crop in the world, nitrogen stress severely reduces maize yield. Although a large number of studies have identified the expression changes of microRNAs (miRNAs) under N stress in several species, the miRNAs expression patterns of N-deficient plants under N resupply remain unclear. Objective The primary objective of this study was to identify miRNAs in response to nitrogen stress and understand relevant physiological changes in nitrogen-deficient maize after nitrogen resupply. Methods Physiological parameters were measured to study relevant physiological changes under different nitrogen conditions. Small RNA sequencing and qRT-PCR analysis were performed to understand the response of miRNAs under different nitrogen conditions. Results The content of chlorophyll, soluble protein and nitrate nitrogen decreased than CK by 0.52, 0.49 and 0.82 times after N deficiency treatment and increased than ND by 0.52, 1.36 and 0.65 times after N resupply, respectively. Conversely, the activity of superoxide dismutase (SOD) and peroxidase (POD) increased by 0.67 and 1.64 times than CK after N deficiency, respectively, and decreased by 0.09 and 0.35 times than ND after N resupply. A total of 226 known miRNAs were identified by sRNA sequencing; 106 miRNAs were differentially expressed between the control and N-deficient groups, and 103 were differentially expressed between the N-deficient and N-resupply groups (P < 0.05). Real-time quantitative PCR (qPCR) was used to further validate and analyze the expression of the identified miRNAs. A total of 1609 target genes were identified by target prediction, and some differentially expressed miRNAs were predicted to target transcription factors and functional proteins. Gene Ontology (GO) analysis was used to determine the biological function of these targets and revealed that some miRNAs, such as miR169, miR1214, miR2199, miR398, miR408 and miR827 might be involved in nitrogen metabolism regulation. Conclusion Our study comprehensively provides important information on miRNA functions and molecular mechanisms in response to N stress. These findings may assist to improve nitrogen availability in plants.

Effect of air flow rate on preparation of boron carbide by sol-gel low-temperature pyrolysis system

Chengcheng Tian,Yang Li,Yuanxia Wang,Ying Shi,Li-Zhi Liu 한양대학교 청정에너지연구소 2024 Journal of Ceramic Processing Research Vol.25 No.2

The morphology and particle size of boron carbide in the sol-gel low-temperature pyrolysis system were controlled bychanging the air flow rate during the pyrolysis of boric acid glycerin system. Analyzed the infrared absorption propertiesof condensation products and pyrolysis products, as well as the carbon network structure of pyrolysis products and themicrostructure, phase composition, and particle size of boron carbide powder. The research results indicate that the airflowing in the pyrolysis atmosphere can accelerate the thermal decomposition efficiency of boric acid glycerol condensate andeffectively reduce the pyrolysis temperature. The faster the air flow rate during the pyrolysis process, the denser the carbonnetwork structure, smaller pore size, and more pores in the pyrolysis products, and the better the dispersion of boron oxide. Inthe boric acid glycerol system, with the increase of pyrolysis gas flow rate, the average particle size of boron carbide decreasesfrom 10 μm to about 2 μm. In addition, the morphology of boron carbide changes from a hexagonal diamond to a smoothermorphology. This indicates that by changing the air flow rate during the pyrolysis process, the carbon network structure ofthe pyrolysis products can be improved, thereby controlling the morphology and particle size of boron carbide. This paperprovides a new method for the study of the sol-gel low-temperature pyrolysis method to accurately control the morphology ofboron carbide.

Preparation of layered B4C with high neutron-shielding properties using graphene as template

Li Yang, Li Sanxi,Wang Song,Tian Chengcheng 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.1

In this paper, layered boron carbide (B4C) particles were successfully synthesized by sol-gel-low temperature pyrolysis methodusing boron acid and glycerin as raw materials with self-made reduced graphene oxide (RGO) as additives. The structure ofthe sol-gel condensation product was analyzed by FT-IR. The phase, morphology and particle size of the B4C werecharacterized by XRD, FE-SEM and LPSA. The results showed that boron carbide was rhombic crystal phase, but the surfaceof the particles was wrinkled and more layered. The B4C powders with uniform morphology and some particle sizes less than100 nm were prepared with the RGO content of 0.6%. Testing the neutron-shielding properties of the polypropylene-B4Ccomposites suggested that neutron transmittance with the B4C content of 35 wt% was 94.1% lower (from 70.6% to 4.1%) thanneat polypropylene, and the total macroscopic absorption cross-section was about 18 times larger (from 0.0857 ± 0.0031 cm-1 to1.5521 ± 0.0008 cm-1). The relative density, fracture toughness and hardness of self-made B4C ceramics (sB4C) were higherthan the commercially available B4C ceramics (cB4C). This study provided a new method for the preparation of B4C powderswith excellent neutron absorption properties and good sintering activity.

Effect of ethylene glycol on the synthesis of crystalline boron carbide powder from condensed boric-acid-glycerin precursor

Li Yang,Li Sanxi,Wang Song,Tian Chengcheng,Otitoju Tunmise Ayode 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.2

The effect of addition of ethylene glycol (C2H6O2) on the synthesis of crystalline boron carbide (B4C) powder from a condensedboric acid (H3BO3)-glycerin (C3H8O3) product was investigated. Equal molar amount of H3BO3 and glycerin was mixed andsubjected to dehydration-condensation reaction using various amount of ethylene glycol (0 to 40 mol% based on glycerolamount). Then the condensed product was thermally decomposed in air twice to obtain surface carbon-free precursor powder. The crystalline phases and surface functional groups of the material was characterized using XRD, SEM, FTIR and TGA. Addition of ethylene glycol offered a new organic sites and comparatively, reduced pyrolysis temperature from 700 to 650 oC. The complete formation of crystalline B4C powder was achieved at 1475 oC within 2.5 h, which is among the shortest timereported for B4C synthesis

Top-squark in natural SUSY under current LHC run-2 data

Han, Chengcheng,Ren, Jie,Wu, Lei,Yang, Jin Min,Zhang, Mengchao Springer-Verlag 2017 European Physical Journal C Vol.77 No.2

<P>We utilize the recent LHC-13 TeV data to study the lower mass bound on the top-squark (stop) in natural supersymmetry. We recast the LHC sparticle inclusive search of (>= 1) jets+E-T with alpha(T) variable, the direct stop pair search (1-lepton channel and all-hadronic channel) and the monojet analyses. We find that these searches are complementary depending on stop and higgsino masses: for a heavy stop the all-hadronic stop pair search provides the strongest bound, for an intermediate stop the inclusive SUSY analysis with alpha(T) variable is most efficient, while for a compressed stop-higgsino scenario the monojet search plays the key role. Finally, the lower mass bound on a stop is: (1) 320 GeV for compressed stop-higgsino scenario (mass splitting less than 20 GeV); (2) 765 (860) GeV for higgsinos lighter than 300 (100) GeV.</P>

Constraining top partner and naturalness at the LHC and TLEP

Han, Chengcheng,Kobakhidze, Archil,Liu, Ning,Wu, Lei,Yang, Bingfang Elsevier 2015 Nuclear Physics, Section B Vol.890 No.-

<P><B>Abstract</B></P> <P>We investigate indirect constraints on the top partner within the minimal fermionic top partner model. By performing a global fit of the latest Higgs data, <SUB> B s </SUB> → <SUP> μ + </SUP> <SUP> μ − </SUP> measurements and the electroweak precision observables we find that the top partner with the mass up to 830 GeV is excluded at 2<I>σ</I> level. Our bound on the top partner mass is much stronger than the bounds obtained from the direct searches at the LHC. Under the current constraints the fine-tuning measure is less than 9% and the branching ratio of T → t Z is bounded between 14% and 25%. We also find that precise measurements of Higgs couplings at 240 GeV TLEP will constrain the top partner mass in multi-TeV region.</P>

Simulating and Analyzing the Effect on Travel Behavior of Residential Relocation and Corresponding Traffic Demand Management Strategies

Haoyang Ding,Min Yang,Wei Wang,Chengcheng Xu 대한토목학회 2018 KSCE Journal of Civil Engineering Vol.22 No.2

Triggered by rapid urban expansion and fast population growth, a progressive residential relocation has occurred in most cities and its impacts on travel behavior have been confirmed in many studies. However, none has evaluated the effects of travel management strategies that relieves the side effects caused by this relocation. To this end, a multi-agent-based simulation model is proposed to assess the impacts of residential relocation on travel behavior and urban transportation in China. Based on the data in Tongling, China, the simulation on six scenarios is conducted to test how the residents in the urban center and suburbs are affected by different strategies, such as increased land diversity in suburbs, lowered growth in private car ownership and improved public transit accessibility. The results indicate that more daily trips would be lengthened and tend to be motorized by this residential relocation. The scenario test shows that compared to other strategies, policies that aims to reduce travel demand and trip distances after residential relocation have a better performance in traffic improvement.

SUSY induced top quark FCNC decay $$t \rightarrow { ch}$$ t → c h after Run I of LHC

Cao, Junjie,Han, Chengcheng,Wu, Lei,Yang, Jin Min,Zhang, Mengchao Springer-Verlag 2014 European Physical Journal C Vol.74 No.9

Stochastic Route Choice Based on VMS Information and Hierarchy for Urban Transport Network

Haoyang Ding,Min Yang,Wei Wang,Chengcheng Xu 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.2

This paper firstly establishes four variational inequalities for stochastic traffic assignment by quantifying information utility of Variable Message Signs (VMS) and hierarchy of transport network. When VMS systems are operated in the higher level of roads such as arterials, the attenuation factor of information utility is integrated with information quantity to define a new formulation of the impact coefficient of VMS on traffic flow, which appears in the definitions of link and path lengths, and allocation parameters. Furthermore, equivalent Variational Inequalities (VIs) of Logit models considering these elements are developed and proved. A case study was conducted using the VI models on a hierarchical road network. We get some practically meaningful results, for example, VMS information can improve hierarchical network performance by interacting with traffic flow in all models except the C-Logit model and hierarchical level can improve network performance. Among the results, the most important is that the C-Logit or pathsize Logit will produce a flow pattern with less fluctuation of traffic densities among links and is less affected by stochastic factors than the multinomial Logit and cross-nested Logit in a stochastic hierarchical road network.