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Effects of Grazing Exclusion on Soil Carbon and Nitrogen Storage in Semi-arid Grassland in Inner Mongolia, China

Chinese Geographical Science 2014年第4期24卷 479-487页

作者： WU Xing LI Zongshan FU Bojie LU Fei WANG Dongbo liu huifeng liu Guohua State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences Environmental Monitoring Center of Hulun Buir

The semi-arid grasslands in Inner Mongolia, China have been degraded by long-term grazing. A series of ecological restoration strategies have been implemented to improve grassland service. However, little is known about the effect of these ecological restoration practices on soil carbon and nitrogen storage. In this study, characteristics of vegetation and soil properties under continued grazing and exclusion of livestock for six years due to a nationwide conservation program—′Returning Grazing Lands to Grasslands(RGLG)′ were examined in semi-arid Hulun Buir grassland in Inner Mongolia, China. The results show that removal of grazing for six years resulted in a significant recovery in vegetation with higher above and below-ground biomass, but a lower soil bulk density and pH value. After six years of grazing exclusion, soil organic C and total N storage increased by 13.9% and 17.1%, respectively, which could be partly explained by decreased loss and increased input of C and N to soil. The effects of grazing exclusion on soil C and N concentration and storage primarily occurred in the upper soil depths. The results indicate that removal of grazing pressure within the RGLG program was an effective restoration approach to control grassland degradation in this region. However, more comprehensive studies are needed to evaluate the effectiveness of the RGLG program and to improve the management strategies for grassland restoration in this area.

关键词： grazing exclusion soil carbon storage soil nitrogen storage grassland management Returning Grazing Lands to Grasslands(RGLG) program semi-arid grassland Hulun Buir grassland

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Effect of fire intensity on active organic and total soil carbon in a Larix gmelinii forest in the Daxing'anling Mountains,Northeastern China

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Journal of Forestry Research 2016年第6期27卷 1351-1359页

作者： Yunmin Wei Haiqing Hu Jiabao Sun Qiang Yuan Long Sun huifeng liu College of Forest Northeast Forestry University 26 He XingRoad Xiangfang District Harbin 150040 China Forest PROTECTION Research Institute in Heilongjiang Province 75Ha Ping Road Xiangfang DistrictHarbin 150040 China College of Life Sciences Northeast Agricultural University59 Wood Street Gongbin Road Xiangfang DistrictHarbin 150030 China College of Agriculture and Forest in Da Xing An Ling Area in Heilongjiang Province Jagedaqi 165000 China

Studying contents and seasonal dynamics of active organic carbon in the soil is an important method for revealing the turnover and regulation mechanism of soil carbon pool. Through 3 years of field sampling and lab analysis, we studied the seasonal variations, content differences, and interrelationships of total organic carbon （TOC）, light fraction organic carbon （LFOC）, and particulate organic carbon （POC） of the soil in the forest areas burned with different fire intensities in the Daxing＇anling Mountains. The mean TOC content in the low-intensity burned area was greater than that in the unburned area, moderate-intensity, and high-intensity burned areas in June and November （P 〈 0.05）. LFOC and POC in the low-intensity burned area were greater than that in either moderate-intensity or high-intensity burned areas, with significant differences in LFOC in September and November （P 〈 0.05）. A significant difference in LFOC between the unburned and burned areas was only found in July （P 〈 0.05）. However, the differences in POC between the unburned and burned areas were not significant in all the whole seasons （P 〉 0.05）. Soil LFOC and POC varied significantly with the seasons （P 〈 0.05） in the Daxing＇anling Mountains. Significant linear relationships were observed between soil TOC, LFOC, and POC, which were positively correlated with soil nitrogen and negatively correlated with soil temperature in the Daxing＇anling Mountains.

关键词： Forest fire intensity Labile organic carbon.Light fraction organic carbon Particulate organic matter carbon Total organic carbon

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Time-averaged sub-layer concentration profiles in oscillatory sheet flows

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International Journal of Sediment Research 2018年第4期33卷 433-440页

作者： Yuhai Wang Wenhong Cao Wen Lu huifeng liu Gauhu Sun Chonghao Wang Fei liu State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research

Although thin on the order of several to tens of millimeters, sheet flows normally comprise a lower pickup sub-layer and an upper contact-load sub-layer, separated at the bed level(z = 0). The time-averaged concentration profile in the pick-up sub-layer shows a 'convex upward' curvature, but 'concave upward'shape characterizes the time-averaged concentration profile in the contact-load sub-layer. The timedependent concentration in the contact-load sub-layer is approximately in-phase with the free stream flow velocity, whereas it is nearly in anti-phase with the free stream flow velocity, in the pick-up sublayer. Two distinct analytical expressions of the time-averaged concentration profiles for the respective sub-layers are proposed. The expressions are validated with detailed observation datasets collected in the Groper Wellenkanal(GWK) prototype wave flume in Hannover, Germany. The agreement between the predicted and the measured values is excellent. Interparticle collisions in the pick-up sub-layer and convective lifting processes associated with vortex shedding in the contact-load sub-layer are considered responsible for the opposite curvatures and in-phase/anti-phase concentration variations. Both transitional boundary and reference concentration are also elaborated.

关键词： Sheet flow Sub-layer Time-averaged concentration profile Suspension mechanism

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CO_(2)LASER PLUS PHOTODYNAMIC THERAPY VERSUS CO_(2)LASER IN THE TREATMENT OF CONDYLOMA ACUMINATUM:A RANDOMIZED COMPARATIVE STUDY

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Journal of Innovative Optical Health Sciences 2012年第1期5卷 61-67页

作者： huifeng liu PING ZHANG XIANGJIE AN liu YANG YAN LI YUJUE WANG FIRAS HAMZE JUAN TAO YATING TU Department of Dermatology Affiliated Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022China Wuhan Institute of Dematosis and Venereal Disease Preventing Wuhan 430030 China

To compare the efficacy and safety of CO_(2)laser plus 5-aminolevulinic acid(ALA)photodynamic therapy(PDT)with CO_(2)laser for the treatment of multiple condyloma acuminatum(CA),120 patients with multiple CA were allocated into two groups—combined group(CO_(2)laser plus ALA-PDT,n=60)and CO_(2)laser group(CO_(2)laser plus placebo-PDT,n=60).After CO_(2)laser,a 20%ALA or a placebo solution was applied to the CA area 3 h before illumination with red light(635 nm,100mW/cm^(2),80 J/cm^(2)).The treatment was repeated seven days after the first treatment if the lesions were not completely *** complete response rate,recurrence rate and adverse effects in the two groups were *** two treatments,the complete response rates in the CO_(2)laser group and combined group were 100%(509/509)and 100%(507/507)in the CA(p>0:05),*** recurrence rates in the CO_(2)laser group and combined group were 44.9%(229/509)and 10.6%(54/507)in the CA(p<0:05),*** adverse effects in CO_(2)laser group was more than that in combined *** combined group is a more effective treatment for multiple CA compared with CO_(2)laser group.T/*** the highlighted text as abstract.

关键词： 5-aminolevulinic acid photodynamic therapy condyloma acuminatum CO_(2)laser

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N-acetylaspartylglutamate Inhibits Heroin Self-Administration and Heroin-Seeking Behaviors Induced by Cue or Priming in Rats

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Neuroscience Bulletin 2017年第4期33卷 396-404页

作者： Huaqiang Zhu Miaojun Lai Weisheng Chen Disen Mei Fuqiang Zhang huifeng liu Wenhua Zhou Laboratory of Behavioral Neuroscience Ningbo AddictionResearch and Treatment Center School of MedicineNingbo UniversityNingbo 315010China

Activation of presynaptic group II metabotropic glutamate receptors（mGluR2/3） inhibits drug reward and drug-seeking behavior, but the role of N-acetylaspartylglutamate（NAAG）, an agonist of endogenous mGluR2/3,in heroin reward and heroin-seeking behavior remained unclear. Here, we aimed to explore the effects of exogenous NAAG on heroin self-administration and heroinseeking behavior. First, rats were trained to self-administer heroin under a fixed ratio 1（FR1） schedule for 10 days,then received NAAG（50 or 100μg/10 μL in each nostril）in the absence or presence of LY341495（1 mg/kg, i.p.）, an antagonist of mGluR2/3, on day 11 and the effects of NAAG on heroin self-administration under FR1 were recorded for 3 consecutive days. Motivation was assessed in heroin self-administration under a progressive ratio schedule on day 11 in another 5 groups with the same doses of NAAG. Additional rats were withdrawn for 14 days after 14 days of heroin self-administration, then received the same pharmacological pretreatment and were tested for heroin-seeking behaviors induced by heroin priming or cues. The results showed that intranasal administration of NAAG significantly decreased intravenous heroin selfadministration on day 12, but not on day 11. Pretreatment with LY341495 prior to testing on day 12 prevented the inhibitory effect of NAAG on heroin reinforcement. The break-point for reward motivation was significantly reduced by NAAG. Moreover, NAAG also significantly inhibited the heroin-seeking behaviors induced by heroinpriming or cues and these were restored by pretreatment with LY341495. These results demonstrated that NAAG,via activation of presynaptic mGluR2/3, attenuated the heroin reinforcement, heroin motivational value, and heroin-seeking behavior, suggesting that it may be used as an adjunct treatment for heroin addiction.

关键词： Glutamate Opioid Metabotropic glutamate receptor Reward Addiction

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Recent advances in catalyst-modified Mg-based hydrogen storage materials

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Journal of Materials Science & Technology 2023年第32期163卷 182-211页

作者： Yaxiong Yang Xin Zhang Lingchao Zhang Wenxuan Zhang huifeng liu Zhenguo Huang Limei Yang Changdong Gu Wenping Sun Mingxia Gao Yongfeng liu Hongge Pan Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province and School of Materials Science and EngineeringZhejiang UniversityHangzhou 310058China School of Civil&Environmental Engineering University of Technology Sydney81 BroadwayUltimoNSW2007Australia

The storage of hydrogen in a compact,safe and cost-effective manner can be one of the key enabling technologies to power a more sustainable *** hydride(MgH_(2))has attracted strong research interest as a hydrogen carrier because of its high gravimetric and volumetric hydrogen ***,the practical use of MgH_(2)for hydrogen storage has been limited due to high operation temperatures and sluggish *** is of crucial importance for the enhancement of hydrogen cycling kinetics of Mg/MgH_(2)and considerable work has been focused on designing,fabricating and optimizing *** review covers the recent advances in catalyzed Mg-based hydrogen storage *** fundamental properties and the syntheses of MgH_(2)as a hydrogen carrier are first briefly *** that,the general catalysis mechanisms and the catalysts developed for hydrogen storage in MgH_(2)are summarized in ***,the challenges and future research focus are *** studies indicate that transition metals,rare-earth metals and their compounds are quite effective in catalyzing hydrogen storage in Mg/MgH_(2).Most metal-containing compounds were converted in situ to elemental metal or their magnesium alloys,and their particle sizes and dispersion affect their catalytic *** in-situ construction of catalyzed ultrasmall Mg/MgH_(2)nanostructures(<10 nm in size)is believed to be the future research *** important insights will help with the design and development of high-performance catalysts for hydrogen storage in Mg/MgH_(2).

关键词： Hydrogen storage Magnesium hydride Kinetics Catalysts Reversibility

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Multi‑omics reveals that the host‑microbiome metabolism crosstalk of differential rumen bacterial enterotypes can regulate the milk protein synthesis of dairy cows

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2496-2513页

作者： Chenguang Zhang Mengya Wang huifeng liu Xingwei Jiang Xiaodong Chen Tao liu Qingyan Yin Yue Wang Lu Deng Junhu Yao Shengru Wu College of Animal Science and Technology Northwest A&F UniversityShaanxi 712100 YanglingChina

Background Dairy cows’lactation performance is the outcome of the crosstalk between ruminal microbial metabo-lism and host ***,it is still unclear to what extent the rumen microbiome and its metabolites,as well as the host metabolism,contribute to regulating the milk protein yield(MPY).Methods The rumen fluid,serum and milk of 12 Holstein cows with the same diet(45%coarseness ratio),parity(2–3 fetuses)and lactation days(120–150 d)were used for the microbiome and metabolome *** metabolism(rumen metabolome)and host metabolism(blood and milk metabolome)were connected using a weighted gene co-expression network(WGCNA)and the structural equation model(SEM)*** Two different ruminal enterotypes,with abundant Prevotella and Ruminococcus,were identified as type1 and *** these,a higher MPY was found in cows with ruminal ***,[Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae(the differential bacteria)were the hub genera of the *** addition,differential ruminal,serum and milk metabolome between enterotypes were identified,where the cows with type2 had higher L-tyrosine of rumen,ornithine and L-tryptophan of serum,and tetrahydroneopterin,palmitoyl-L-carnitine,S-lactoylglutathione of milk,which could provide more energy and substrate for ***,based on the identi-fied modules of ruminal microbiome,as well as ruminal serum and milk metabolome using WGCNA,the SEM analysis indicated that the key ruminal microbial module1,which contains the hub genera of the network([Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae)and high abundance of bacteria(Prevotella and Ruminococcus),could regulate the MPY by module7 of rumen,module2 of blood,and module7 of milk,which contained L-tyrosine and ***,in order to more clearly reveal the process of rumen bacterial regulation of MPY,we established the path of SEM based on the L-tyrosine,L-tryptophan and related *** SEM based on th

关键词： Dairy cows Microbial and host metabolome Milk protein Ruminal microbiota enterotype Structural equation model Weighted gene co-expression network

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A fusion attitude determination method based on quaternion for MEMS gyro/accelerometer/magnetometer

A fusion attitude determination method based on quaternion f...

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第25届中国控制与决策会议

作者： Zhou Yongjie Zhang Haiyun ZhangTao Wang Leigang Ren Wei Luan Mengkai liu huifeng Shi Jingwei Tsinghua Space Center Tsinghua University Department of Automation School of Information Science and Technology Tsinghua University NEC Labs China

ISBN: (纸本)9781467355339

With the development of new technologies and market demand changing, MEMS gyroscope has been widely used. But low accuracy, large drift and other defects limit its application in some areas. This paper presents an attitude fusion algorithm based on the MEMS gyroscope, MEMS accelerometer and MEMS magnetometer. Firstly, the error model of the MEMS gyroscope was established, and rotation vector method to determine the gyro attitude was introduced. Then the state equation and observation equation of the designed Kalman filter was derived. Finally, experimental results illustrated the effectiveness of the fusion algorithm. That is, with the proposed fusion attitude determination algorithm, it is able to compensate gyro drift and provide a reliable and stable attitude for a long time.

关键词： MEMS gyro drift rotation vector method Kalman filter fusion attitude determination

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税收优惠对文化资本配置的影响——基于文化企业并购视角的研究

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山东大学学报（哲学社会科学版） 2019年第3期 44-57页

作者：刘慧凤山东大学管理学院

为了促进文化产业的发展,中央和地方政府出台了系列税收优惠政策。文化企业享受的税收优惠不仅有来自文化产业多税种的制度优惠,还有来自地方政府的税收返还。税收优惠政策客观上形成了文化企业政策环境的行业比较优势与区域差异,这种... 详细信息

为了促进文化产业的发展,中央和地方政府出台了系列税收优惠政策。文化企业享受的税收优惠不仅有来自文化产业多税种的制度优惠,还有来自地方政府的税收返还。税收优惠政策客观上形成了文化企业政策环境的行业比较优势与区域差异,这种税收优惠上的差异化格局为文化企业通过并购进行资源整合和制度套利提供了机会。已有聚焦于所得税政策优惠与企业并购相关性的研究成果尚未客观反映税收政策的激励效果。以2011■2016年文化企业上市公司数据为样本研究发现:税收优惠能促发文化企业并购行为,并购后企业税负显著下降,财务业绩(ROE)得到提升;税收优惠也能促发跨行业并购,跨行业并购后企业税负虽然没有显著降低,但通过业务多元化分工协作,能够显著提高企业财务业绩;但税收优惠抑制了文化企业跨地区并购,跨地区并购能显著降低企业并购后税负,但未能显著提升财务业绩。企业产权性质、多元化程度和区域环境影响税收优惠政策的激励效果。

关键词：文化企业税收优惠跨地区并购跨行业并购资本配置效果

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长周期变动中的技术革命与产业演进——基于历史与统计的分析

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中国科技论坛 2009年第4期 8-13页

作者：刘辉锋中国科学技术发展战略研究院北京100038

本文以创新和演化经济学的长周期理论为基础,基于历史与统计的分析视角,围绕长周期变动中的技术革命和主导产业的演变,对工业革命以来的五次长周期的基本特征、技术革命的作用、技术-经济范式的转换等问题作了讨论和阐述。一般而言,每... 详细信息

本文以创新和演化经济学的长周期理论为基础,基于历史与统计的分析视角,围绕长周期变动中的技术革命和主导产业的演变,对工业革命以来的五次长周期的基本特征、技术革命的作用、技术-经济范式的转换等问题作了讨论和阐述。一般而言,每一轮技术革命爆发后都会引发经济过热和金融泡沫,并促进大量资本向生产领域的回归。当前遍及全球的金融和经济危机,必将带来国家对金融和经济的强有力干预及监管,并通过不同程度的制度和组织重构,推动经济走向复苏和繁荣。

关键词：长周期技术革命产业演进危机

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