Synthesis of high density and low freezing point jet fuels range cycloalkanes with cyclopentanone and lignin-derived vanillins

In this work,a“cyclopentanone-vanillin”strategy was proposed for the preparation of jet fuel range cycloalkanes from lignocellulose-derived ketones and lignin-derived aldehydes via aldol condensation and hydrodeoxygenation(HDO).Ethanolamine lactate ionic liquid(LAIL)exhibited excellent catalytic activity in the aldol condensation of cyclopentanone and vanillin.Desired mono-condensation and bicondensation products were obtained with yield of 95.2%at 100℃.It is found that the synergy effects between amino group of ethanolamine and hydroxyl group of lactic acid play a key role in the aldol condensation.The condensation products were converted into cycloalkanes by HDO over 5%Pd/Nb_(2)O_(5)catalyst.The density of the obtained HDO products is 0.89 g/cm^(3)and the freezing point is lower than-60℃.These results suggest that the resulted cycloalkanes can be used as additives to improve the density and low-temperature fluidity of the jet fuels.

Genetic improvement of legume roots for adaption to acid soils

Acid soils occupy approximately 50% of potentially arable lands.Improving crop productivity in acid soils,therefore,will be crucial for ensuring food security and agricultural sustainability.High soil acidity often coexists with phosphorus(P) deficiency and aluminum(Al) toxicity,a combination that severely impedes crop growth and yield across wide areas.As roots explore soil for the nutrients and water required for plant growth and development,they also sense and respond to below-ground stresses.Within the terrestrial context of widespread P deficiency and Al toxicity pressures,plants,particularly roots,have evolved a variety of mechanisms for adapting to these stresses.As legumes,soybean(Glycine max) plants may acquire nitrogen(N) through symbiotic nitrogen fixation(SNF),an adaptation that can be useful for mitigating excessive N fertilizer use,either directly as leguminous crop participants in rotation and intercropping systems,or secondarily as green manure cover crops.In this review,we investigate legumes,especially soybean,for recent advances in our understanding of root-based mechanisms linked with root architecture modification,exudation and symbiosis,together with associated genetic and molecular strategies in adaptation to individual and/or interacting P and Al conditions in acid soils.We propose that breeding legume cultivars with superior nutrient efficiency and/or Al tolerance traits through genetic selection might become a potentially powerful strategy for producing crop varieties capable of maintaining or improving yields in more stressful soil conditions subjected to increasingly challenging environmental conditions.

Genome assembly of KA105,a new resource for maize molecular breeding and genomic research

Superior inbred lines are central to maize breeding as sources of natural variation.Although many elite lines have been sequenced,less sequencing attention has been paid to newly developed lines.We constructed a genome assembly of the elite inbred line KA105,which has recently been developed by an arti-ficial breeding population named Shaan A and has shown desirable characteristics for breeding.Its pedigree showed genetic divergence from B73 and other lines in its pedigree.Comparison with the B73 reference genome revealed extensive structural variation,58 presence/absence variation(PAV)genes,and 1023 expanded gene families,some of which may be associated with disease resistance.A network-based integrative analysis of stress-induced transcriptomes identified 13 KA105-specific PAV genes,of which eight were induced by at least one kind of stress,participating in gene modules responding to stress such as drought and southern leaf blight disease.More than 200,000 gene pairs were differentially correlated between KA105 and B73 during kernel development.The KA105 reference genome and transcriptome atlas are a resource for further germplasm improvement and surveys of maize genomic variation and gene function.

LINC00609 inhibits A549 cells progression through the regulation of miR-128-3p/RND3 axis

Background:Long-chain non-coding RNA(lncRNA)LINC00609 is a potential tumor suppressor,but the mechanism of action in non-small cell lung cancer(NSCLC)is yet to be understood.Objectives:The effects of LINC00609 on A549 cell proliferation,apoptosis,and cell cycle arrest were investigated.Methods:The LINC00609 levels in NSCLC and normal tissues were analyzed by bioinformatics.Expressions of LINC00609,miR-128-3p,and Rho family GTPase 3(RND3)in NSCLC cells(A549)were determined by qRT-PCR.Bioinformatics analysis predicted target genes and dual-luciferase reporter assays to ensure that LINC00609 targeted miR-128-3p and miR-128-3p targeted RND3.The proliferation of cells was determined using EDU and CCK-8.Flow cytometry was used to evaluate cell apoptosis rate and cell cycle.The western blotting assay identified proteins related to proliferation and apoptosis.Results:In NSCLC tissues,LINC00609 was expressed in low levels,while its high expression was associated with a higher survival rate.LINC00609 affected cell proliferation,apoptosis,cell cycle arrest,and expression of related proteins.Dual-luciferase reporter assay showed that LINC00609 binds specifically to miR-128-3p,and miR-128-3p binds to RND3.MiR-128-3p overexpression could neutralize the effects of LINC00609.A siRNA targeting RND3 could reverse the effect of the miR-128-3p inhibitor.Silencing RND3 resulted in a decrease in apoptosis rate and the number of cells in the S-phase and an increase in the number of cells in the G1-phase.Furthermore,phosphorylation levels of the AKT protein and mTOR protein,and Bcl2 expression,increased;however,the expression of RND3,Bax,and caspase3 decreased.Conclusions:LINC00609 regulated miR-128-3p/RND3 axis to modulate A549 cell proliferation,apoptosis,and cell cycle arrest.In the case of NSCLC,LINC00609 could be a potential target for therapy.

高结构稳定性、低泄漏率三维铜@石墨烯复合相变材料的制备

由于能源消费需求的持续增长和传统化学燃料的日益枯竭,对可再生能源的需求日益迫切。以地热能、太阳能为代表的可再生能源脱颖而出。然而,这些能源的应用易受到天气、季节、地点和时间的影响,具有不稳定性、随机性、波动性和间歇性。储能技术是解决上述问题的有效途径,它可以在需要的时候储存或释放能量。在各种储能技术可选材料中,相变材料(PCMs)是智能热能管理和便携式热能领域的有力候选者。大多数相变材料都存在导热系数低、环境污染、熔点泄漏等问题,因此有必要将相变材料封装到支撑骨架材料中。事实上,支撑材料在应用中仍面临着一些重大挑战。首先,骨架材料应能抵抗相变材料在相变过程中的体积变化,即具有良好的结构稳定性。其次,还应具有较高的导热系数和较低的泄漏率。石墨烯气凝胶(GA)已被证明是提高相变材料形状稳定性的有效支撑骨架,但相变引起的泄漏和网络结构的脆性是制约其应用的关键问题。在此,我们提出了一种双脉冲电镀的强化策略,用于制备铜@石墨烯气凝胶(Cu@GA)作为相变储能骨架材料。这一结构设计中,石墨烯气凝胶上的石墨烯片层上均匀地镀上了铜层,且不同片之间被铜镀层所连接。这种铜增强石墨烯气凝胶网络结构赋予复合材料良好的导热性和坚固的骨架稳定性,有利于增强相变换热和抑制相变过程中的泄漏。此外,通过真空浸渍法将十八胺(ODA)封装在Cu@GA骨架中,获得了结构稳定性高、泄漏率低的复合相变材料(Cu@GA/ODA),保证了ODA在Cu@GA骨架材料中的均匀分散和填充。通过比较复合相变材料的重量变化,研究了不同骨架对复合相变材料泄漏率的影响。优化后的复合相变材料(CPCM)Cu@GA/ODA经20次储热、放热循环后,泄漏率降低至19.82%(w,质量分数),而GA/ODA和GOA/ODA为骨架的复合相变材料的泄漏率分别为80.31%(w)和72.99%(w)。为了探讨这种影响的原因,用扫描电子显微镜(SEM)观察了循环后骨架的形貌。铜/石墨烯气凝胶(Cu@GA)骨架材料没有明显的收缩或坍塌,仍可以保持完整的三维网络结构,而氧化石墨烯气凝胶(GOA)和石墨烯气凝胶(GA)的骨架材料三维结构不复存在,且在氧化石墨烯/石墨烯片能够观察到明显的裂隙。铜涂层可以提高骨架的微观结构稳定性,有利于提高结构稳定性,降低复合材料的泄漏率。同时,该研究为构建理想的金属增强石墨烯气凝胶复合骨架材料铺平了新的道路,该复合材料具有优异的综合性能,可用于未来的相变储能、多孔微波吸收和储能应用。

中国西南地区3个隔离人群遗传亚结构分析

中国西南地区分布着众多少数民族,同时也包含许多地理和遗传隔离的人群,然而这些族群的遗传结构,特别是父系遗传结构缺乏深度解析。本研究采用Y染色体捕获及Illumina测序技术,对西南地区3个隔离人群男性无关个体样本,包括四川平武县的白马人、石棉县的木雅人及云南景洪市空格人,通过定点复合扩增检测,直接计数法计算相关单倍群频率,应用Past3.0软件进行PCA(principle component analysis,PCA)主成分分析并绘制群体聚类树,研究了3个族群的父系遗传结构,并探讨其遗传亚结构关系。本研究共观察到云南空格人三种Y染色体单倍群、四川白马人四种Y染色体单倍群以及木雅人五种Y染色体单倍群。结果表明,空格人与佤族的父系遗传关系最近;而白马人和木雅人主要集中在D单倍群及其下游,研究提示着白马人和四川羌族的父系遗传关系最近;木雅人与昌都地区藏族和林芝地区藏族父系遗传关系最近。本文对不同族群遗传结构的分析,丰富了我国隔离人群遗传关系的研究成果。

Performance of a 4 cm iodine-fueled radio frequency ion thruster

The performance of an iodine radio ion thruster with a 4 cm diameter(IRIT4)was studied experimentally in this paper.Regulation of the mass flow rates of the iodine propellant is achieved by using a temperature control method of the iodine reservoir.Performance of the thruster using iodine as propellants is obtained at different total thruster powers of 40.6–128.8 W,different grid voltages of 1000–1800 V and the iodine flow rate of 100μgs^(-1).Results show that thrust and specific impulse increase approximately linearly with the increasing total thruster power and the screen grid voltage.The thrust of 2.32 mN and the specific impulse of 2361 s are obtained at the nominal total thruster power of 95.8 W and the screen grid voltage of 1800 V.It is also indicated that performance of the iodine propellant is comparable to that of the xenon propellant;and a difference between them is that the iodine thrust is slightly higher than xenon when the total thruster power is more than 62 W.At the nominal 95.8 W total thruster power,the thrust values of them are 2.32 m N and 2.15 mN respectively,and the thrust-to-power ratios of them are 24.2 mN kW^(-1)and 23.5 mN kW^(-1),respectively.

Two-step Structural Design of Mesh Antennas for High Beam Pointing Accuracy

A well-designed reflector surface with high beam pointing accuracy in electromagnetic performance is of practical significance to the space application of cable mesh reflector antennas. As for space requirements, cir- cular polarizations are widely used in spaceborne antennas, which usually lead to a beam shift for offset reflectors and influence the beam pointing accuracy. A two-step structural design procedure is proposed to overcome the beam squint phenomenon for high beam pointing accuracy design of circularly polarized offset cable mesh reflectors. A simple structural optimal design and an integrated structural electromagnetic optimization are combined to alleviate the beam squint effect of circular polarizations. It is imple- mented by cable pretension design and adjustment to shape the offset cable mesh surface. Besides, in order to increase the efficiency of integrated optimization, an update Broy- den-Fletcher-Goldfarb-Shanno （BFGS） Hessian matrix is employed in the optimization iteration with sequential quadratic programming. A circularly polarized offset cable mesh reflector is utilized to show the feasibility and effectiveness of the proposed procedure. A high beam pointing accuracy in order of 0.0001~ of electromagnetic performance is achieved.

In situ synthesis of biomass-derived Ni/C catalyst by self-reduction for the hydrogenation of levulinic acid to γ-valerolactone

Herein,we reported in situ synthesis of biomass-derived Ni/C catalyst by self-reduction with pomelo peel.Compared with the conventional method, which includes carbonization, activation, impregnation and reduction, the entire preparation process was simplified to two steps, which was more straightforward. This synthesis method was green as Ni/C can be prepared without any additional chemical and the self-reduction process was realized in N2, which can avoid using H2 thus averting some problems such as storage, transportation and safety of H2. Meanwhile, the size and dispersion of Ni particles can be controlled by changing carbonization temperature.The synthesis mechanism of Ni/C catalyst with selfreduction was investigated, which was mainly attributed to the carbon and reducing gas produced during the carbonization process.For the catalytic performance of GVL synthesis, a high yield (94.5%) can be obtained and it exhibited good stability up to 5 cycles without obvious loss of catalytic activity.

Influence of anode temperature on ignition performance of the IRIT4-2D iodine-fueled radio frequency ion thruster

This paper reports the ignition performance of the iodine-fueled radio frequency(RF)ion thruster(IRIT)at different anode temperaturesT_(a0).The experimental results show that the anode temperature plays important role on the ignition process of the IRIT.There were two characteristic temperatures related to the anode:the minimum ignition temperatureT_(i0)and the stable ignition temperatureT_(is),which were much lower than the pipeline temperature and the storage tank temperature.AtT_(a0)<T_(i0),it failed to discharge.WhenT_(i0)≤T_(a0)<T_(is),it was ignited with dramatical oscillations.AtT_(a0)≥T_(is),the discharge was stable in a large anode temperature range.The analysis showed that the different discharge phenomena at different anode temperatures were attributed to the change of iodine flow rate during the process of the iodine deposition-clogging and sublimation-clearing inside the thruster.The research helps improve the preheating design of the iodine-fueled electric thruster.

Understanding the geometric and electronic factors of PtNi bimetallic surfaces for efficient and selective catalytic hydrogenation of biomass-derived oxygenates

Ni-base catalysts are promising candidate for the hydrogenation of furfural(FAL) to high-value chemicals.However,slow intermediate desorption and low selectivity limit its implementation.Identifying the catalytic performance of each active sites is vital to design hydrogenation catalyst,and tuning the geometrical sites at molecule level in PtNi could lead to the modification of electronic structure,and thus the selectity for the hydrogenation of FAL was modulated.Herein,PtNi hollow nanoframes(PtNi HNFs) with three dimensional(3 D) molecular accessibility were synthesized,EDX results suggested that Ni was evenly distributed inside of the hollow nanoframes,whereas Pt was relatively concentrated at the edges.DFT calculation demonstrated that PtNi significant decrease the desorption energy of the intermediates.This strategy could not only enhance the desorption of intermediates to improve the catalytic performance,but also transfer the adsorption mode of FAL on catalyst surface to selective hydrogenation of FAL to FOL or THFA.The PtNi HNFs catalyst afforded excellent catalytic performance for selective hydrogenation of a broad range of biomass-derived platform chemicals under mild conditions,especially of FAL to furfuryl alcohol(FOL),in quantitative FOL yields(99%) with a high TOF of 2.56 h^(-1).It is found that the superior performance of PtNi HNFs is attributed to its 3 D hierarchical structure and synergistic electronic effects between Pt and Ni.Besides,the kinetic study demonstrated that the activation energy for hydrogenation of FAL was as low as 54.95 kJ mol^(-1).

直接融资发展对“卢卡斯悖论”的消解作用——基于细分渠道跨区域资本流动的研究

发展直接融资,实现资源优化配置是建设高标准市场体系的应有之义。随着我国金融市场的发展,跨区域资本流动渠道日益多样化、复杂化,不同渠道的跨区域资本流动是否存在"卢卡斯悖论"?直接融资发展是否能够消解"卢卡斯悖论"现象,实现资源优化配置?本文从股市、债市、银行和财政四个细分渠道跨区域资本流动的视角出发,探究了直接融资发展对"卢卡斯悖论"的作用机制,发现直接融资的发展能够消解"卢卡斯悖论"现象,优化跨区域资本配置。具体而言,不同渠道的跨区域资本流动对"卢卡斯悖论"现象的贡献不同,从而导致了"卢卡斯悖论"现象随时间而动态变化,并且在不同地区呈现显著差异。股市、债市渠道资金与资本回报率正向流动,这一正向关系随时间显著增强,由此削弱了资本流动的"卢卡斯悖论"现象;银行、财政渠道资金与资本回报率逆向流动,存在资本流动的"卢卡斯悖论"现象,但这一反向关系随时间明显削弱。市场化程度更高的地区资本流动的"卢卡斯悖论"现象更弱,直接融资对"卢卡斯悖论"现象的消解作用更强。

职业教育数字化赋能提质研究

在全球产业数字化不断升级的大环境下,以及疫情防控呼唤职业教育数字化转型的现实需求下,基于产教融合、校企合作开展职业教育数字化转型势在必行,数字化转型也是提高教学质量、推进教育创新、实现职业教育现代化的必经之路。根据“整体规划、系统推进、分步实施”的职业教育数字化转型思路,按照“源→算→现→用”的实施路径,结合各个职业院校的实际情况,采取切实有效的数字化转型措施,循序渐进、持续迭代、循环推进职业教育数字化转型,为职业教育提质培优奠定坚实基础。

Performance and stability of yield in response to plant density,year and location in maize hybrids of Northwest China

Identifying desirable genotypes with the best performance in diverse environments is a perpetual aim of plant breeding,and the interaction between genotype and environment(G×E)always plays a key role.This study was conducted to elucidate the genetic behaviour of different hybrid combinations at various densities in diverse environments.According to a line×tester design,32 hybrid combinations were obtained from 16 inbred individuals crossed with two testers and planted at three locations at three density levels(45,000,67,500 and 90,000 plants ha-1)during 2014-2017.Genotype(G),environment(E)and the interaction of genotype and environment(G×E)significantly affected grain yield at different densities.Increasing planting density enhanced grain yield and improved the efficiency of germplasm screening,where the effect of location on grain yield at different densities was larger than that of year and the GCA was larger than the SCA.Finally,four inbred lines(KB102,KB081,KA105,and KB106)with a high GCA,environmental adaptability,and several combinations using them as parents have been approved in ShannXi Province and National of China.In conclusion,the evaluation of combining ability at multiple densities and locations can effectively screen inbred lines and improve breeding efficiency.

One-pot synthesis of Fe_(x)O_(y)nanoparticles embedded within N-doped carbon layers as highly efficient and selective catalysts for the hydrogenation of nitroarenes

Inhibiting the side reactions while promoting hydrogenation are the main target for the production of functional anilines from nitroarenes;consequently,the preparation of an ideal catalyst to improve chemical selectivity is one of the hot issues.In this work,we provided an easy-to-prepare catalyst with Ndoped carbon layers,where the Fe_(x)O_(y)nanoparticles were encapsulated and distributed uniformly.The structural features of catalyst were characterized by several techniques,and the selected catalyst was next applied to the hydrogenation of nitrobenzene under varied conditions,involving temperature,holding period and H2 pressure.Subsequently,we conducted the synthesis of more than 16 substrates for the corresponding anilines with varied functional groups.The hydrogenation protocol to gram-scale synthesis as well as lifecycle performance were also demonstrated in the batch reactor,together with the explanation of its catalytic mechanisms.Overall,the present work provides an available preparation of simple but highly efficient catalysts for the production or aromatic amines,which will be benefit for the sustainable development of this field in near future.

高热沉碳氢喷气燃料吸热反应研究进展

高超音速飞行器是空天领域的重要发展方向,是国家整体科技实力的重要标志。吸热型碳氢燃料为兼具冷却与推进功能,需要具备高热沉、高密度、高热值、高热安定性、低冰点、低结焦和低成本的“四高三低”的基本特征。本文总结了吸热型碳氢燃料吸热反应研究进展,重点关注热裂解、催化裂解和催化蒸汽重整对于热沉的影响,分析了温度、压力和停留时间等热解条件对热沉的影响,考察了燃料组成、分子结构与热裂解间的关联规律,总结了分子筛、纳米颗粒和引发剂对吸热型碳氢燃料催化裂解行为和热沉的影响特性,并对吸热反应过程中的结焦及抑制技术进行了总结,结合发展现状提出了吸热型碳氢燃料未来的研究方向。

Application of different molecular sieves in photothermal catalysis of Jatropha oil

The preparation of green and economical bio-aviation fuel is a priority for the sustainable development industry.In this study,Jatropha oil was used as a raw material to catalyze the conversion of raw material to aviation kerosene fraction by photothermal coupling under the conditions of light and low temperature.The correlations among conversion rate,target alkane selectivity,composition distribution,and catalyst microstructure were investigated by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),nitrogen(N2)adsorption and desorption,X-ray fluorescence(XRF),ammoniatemperature programmed desorption(NH3-TPD),ultraviolet-visible spectrophotometry(UV-Vis),and other characterization.The correlation between conversion and target alkane selectivity and composition distribution and catalyst microstructure was investigated,and different modification methods and different molecular sieve materials were selected.The results showed that the molecular sieves modified with the solid dispersion method could retain the structural stability of titanium dioxide(TiO2)and molecular sieves to a great extent while slightly enhancing the pore capacity and pore size of the catalyst to make it easier to adsorb reactants;the introduction of active metal platinum(Pt)could reduce the forbidden bandwidth of the catalyst,increase the weak acid amount of the catalyst,improve the adsorption capacity of hydrogen(H2),and thus improve the catalytic ability,resulting in a suitable catalyst for this study:P-21.The photothermal catalytic reaction of Jatropha oil using P-21 catalyst obtained 97.21%conversion and 74.99%selectivity of the target alkanes under the optimal process parameters.The results of this study provide effective catalyst parameters for research in the field of clean energy.

人种的客观存在

目前,学术界对人种概念存在否定和认同两种截然不同的看法.对人种不同看法的产生,与对人种的定义理解不同有关.否定人种的学者,是把不同人种看成生物学上的不同物种.人种问题是学术问题,是可以讨论的.人种这个名词在社会生活中仍在被广泛使用.人种问题与种族主义问题不能混淆在一起.地球上所有现代人都是同一物种.人种是具有共同遗传体质特征的人类群体.人种概念并不是生物学上的物种概念,而是地理种的概念.在现代人诞生后,分散、迁徙到世界不同地区.不同地区的环境对各个人群迁徙支系的遗传变异进行选择,逐渐形成了现代人的不同地理种,也就是我们说的人种.划分人种并非只依靠一个性状,而是对多个性状进行综合考虑.学术界采用宏观的形态学指标,如肤色、发色、眼色、鼻型、唇、头型、面型、肤纹、耵聍以及血型等指标对人种进行描述和分类.单核苷酸多态性、基因拷贝数量多态性有助于不同人种的形成.本研究通过对蒙古族、北方汉族、傣族的头面部形态学指标以及身高的测量和观察,证实北亚类型族群、东亚类型族群、南亚类型族群的头面部特征存在明显的差异.研究发现,北亚类型族群身材较高、头较宽、鼻较窄、唇较薄,南亚类型族群身材较矮、鼻较宽、唇较厚,东亚类型族群头面部特征介于北亚类型族群和南亚类型族群之间.否定人种的学者,实际否定人种是不同的物种,无法否定现代人的地理种的存在,无法否定不同地理种之间明显的形态学差异.由于人种之间的差别是地理种差别,所以各个人种基因组差异自然很小.不同人种间的DNA序列99.9%相同,然而,正是这0.1%左右的DNA序列差异,导致人种的划分.目前,尽管人种之间融合速度加快.不同人种之间性状差异还是很明显的.人种的主要特征并没有消失.人种之间的差异还会长期存在.人种概念已经过时的说法是不符合客观现状的.

G-CSF is a key modulator of MDSC and could be a potential therapeutic target in colitis-associated colorectal cancers

Granulocyte colony-stimulating factor （G-CSF） is an essential regulator of neutrophil trafficking and is highly expressed in multiple tumors. Myeloid derived suppressor cells （MDSCs） promote neoplastic progression through multiple mechanisms by immune suppression. Despite the findings of G-CSF function in colon cancer progression, the precise mechanism of G-CSF on MDSCs regulation and its blockade effects on tumor growth remains a worthy area of investigation. In this study we observed an overexpression of G-CSF in a mouse colitis-associated cancer （CAC） model, which was consistent with the accumulation of MDSCs in mouse colon tissues. Further in vitro studies demonstrated that G-CSF could promote MDSCs survival and activation through signal transducer and activator of transcription 3 （STAT3） signaling pathway. Moreover, compared with isotype control, anti-G-CSF mAb treatment demonstrated reduced MDSC accumulation, which led to a marked decrease in neoplasm size and number in mice. Our results indicated that G-CSF is a critical regulating molecule in the migration, proliferation and function maintenance of MDSCs, which could be a potential therapeutic target for cancer.

Body weights in Han Chinese populations

The body weights of 26,954 Han Chinese adults in 67 areas(16,503 in rural areas and 10,451 in urban areas) across China were measured from 2009 to2013.The results showed that in China,the three areas(north China,northeast China,and Jianghuai Plain) were with the greatest body weight.Northwest Han Chinese populations were heavier.Southwestern dialect groups were at the middle level and lighter than northern Han Chinese populations,but were heavier among southern Han Chinese populations.Chinese Han who located in areas of Hangjiahu were the general level,and similar to southwestern dialect groups.The mean values of body weight in Hunan Han and Fujian Han were greater than other Han groups in southern China.Gan dialect groups and Cantonese dialect groups showed the minimum body weightvalue in all Chinese Han groups.Besides,the mean body weight of Hakka was heavier than Gan dialect groups and Cantonese dialect groups which were adjacent to Hakka.Body weight increases with an increase in height,bone diameter,subcutaneous fat on the limbs and trunk,chest circumference,and abdomen circumference.This study revealed that northern Han men were heavier than southern Han men,because the former were taller and had a larger waist circumference as well as thicker subcutaneous fat on their backs.Among women,height,bone diameter of the upper limbs,chest and abdomen circumferences,and subcutaneous fat on the limbs and trunks of northern Han exceeded those of rural southern Han.Consequently,body weight values of northern Han women were higher than those of southern Han women.While a significant difference in these values was found between urban and rural men,no significant difference occurred between urban and rural women.Body weight was associated with age in urban and rural men only in the case of minority groups.However,there was a positive correlation between body weight and age in the majority groups of both urban and rural women.The particular composition of genes involved in body weight traits of Han populations across the country has created a genetic foundation accounting for varying body weights of different Han populations.Environmental factors also play a role.As the Han are widely dispersed,their habitation areas vary according to factors such as topography,temperature,precipitation,humidity,and light.Moreover,labor intensity,food composition,and the intake of various nutrients also differ across Han populations.All of these factors have affected the development of body weight in Han populations living in different locations.