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Assessing current stocks and future sequestration potential of forest biomass carbon in Daqing Mountain Nature Reserve of Inner Mongolia, China

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Journal of Forestry Research 2016年第4期27卷 931-938页

作者： Yahui Sun li Meng lü tian Guoliang li Osbert Jianxin Sun College of Forest Science Beijing Forestry UniversityBeijing 100083 China Survey and Planning Institute of State Forestry Administration Beijing 100714 China Inner Mongolia Institute of Forest Monitoring and Planning Huhhot 010020 China Institute of Forestry and Climate Change Research Beijing Forestry University Beijing 100083 China

Assessment of regional forest carbon stocks and underlying controls is critical for guiding forest management in the context of carbon sequestration. We investigated the variations in tree biomass carbon stocks relating to forest types, and estimated the total tree biomass carbon stocks and projected gains through natural stand development by 2020 and 2050 in the Daqing Mountain Nature Reserve based on Category II data of the Forest Inventory of Inner Mongolia for the period ending 2008. Over a total area of 388,577 ha,this nature reserve currently stores an estimated 2221 Gg C in tree aboveground biomass alone, with potential to grow by more than 30 % to reach 2938 Gg C by 2020 and nearly double to 4092 Gg C by 2050 through natural development of the existing forest stands. The tree biomass carbon density and potential gain in tree biomass carbon stocks vary markedly among forest types and with stand *** variations in the potential change of tree biomass carbon density for the periods 2008–2020 and 2008–2050 among forest types partly reflect the varying relationships of tree biomass carbon density with stand age for different tree species, and partly are attributable to variations in the stand age structure among different forest types. Of the major forest types, the ranking of projected changes in tree biomass carbon density are not consistent with variations in the relationship between tree biomass carbon density and stand age, neither are they explainable by variations in stand age structures, implying the interactive effect between forest type and stand dynamics on temporal changes in tree biomass carbon density. Birch rank highest for future biomass carbon sequestration because of its dominance in cover area and better age structure for potential gain in tree biomass carbon stocks. Poplar and larch were out-performers compared to other forest types given their greater contribution to total tree biomass carbon stocks relative to their distributional

关键词： sequestration biomass stocks stand forests Reserve Birch projected gains anthropogenic

EFFECT OF Cu-Ni CONTENT ON THE CORROSION RESISTANCE OF(Cu-Ni)/(10NiO-90NiFe_2O_4)CERMET INERT ANODE FOR AlUMINUM ElECTROlYSIS

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Acta Metallurgica Sinica(English letters) 2008年第1期21卷 72-78页

作者： Z.l. tian Y.Q. lai J. li Y.X. liu School of Metallurgical Science and Engineering Central South University Changsha 410083 China

（Cu-Ni）/（10NiO-90NiFe204） cermet inert anodes containing metal Cu-Ni0, 5, 10, 15 and 20 wt pct were prepared and their corrosion resistance to Na3AlF6-Al2O3 melts was investigated. The results indicate that the content of metal Cu-Ni has little effect on the steady-state concentration of Ni in the electrolyte and the values could not be used to effectively differentiate their corrosion resistance. The steady-state concentration of Fe decreases from 304×10^-6 to 168×10^-6 and that of Cu increases from 21×10^-6 to 71×10^-6 with the content of metal Cu-Ni increasing from 0 to 20 wt pct. Post-examination shows that metallic phase Cu-Ni is corroded preferentially during electrolysis and many pores are left at the anode surface. Considering the corrosion resistance and electrical conductivity, the cermet containing metal Cu-Ni 5 wt pct should be selected and studied further.

关键词： Aluminum electrolysis Inert anode NiFe2O4 based cermet Corrosion resistance

MICROSTRUCTURE TRANSFORMATION IN THE WElDING HEAT AFFECTED ZONE OF 800MPa GRADE UlTRA FINE STRUCTURED STEEl

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Acta Metallurgica Sinica(English letters) 2004年第3期17卷 238-246页

作者： J.B. liu l.J. Hu Y.T.Wang Z. Q. liu K. Miao Z.l. tian Huazhong University of Science and Technology Wuhan 430074 China Technology Center of Wuhan Iron and Steel (Group) Corporation Wuhan 430080 China Central Iron and Steel Research Institute Beijing 100080 China

The transformation behavior and microstructure development in the heat affected zone(HAZ)of 800MPa grade ultra fine structured steel was *** was found that the HAZ has intermediate temperature transformation characteristics in a wide range of cooling rates,with the bainite sheaves consisting of bainite ferrite plates without carbide precipitation and retained austenite in the fast cooling *** relatively high cooling rates,which corresponded to low heat inputs,the hardness of the simulated HAZ was above that of the base *** the cooling rate was below 9C/s,the welding HAZ would have an obvious *** analysis of transformation rates in continuous cooling processes was completed by numerical differential *** result indicated that the microstructure transformation rate of the HAZ in 800MPa grade ultra fine structured steel changed sharply to slow speeds when the cooling time t8/5 is longer than 7s.

关键词： ultra fine structured steel weld heat affected zone transformation rate microstructure

The priority of management factors for reducing the yield gap of summer maize in the north of Huang-Huai-Hai region, China

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Journal of Integrative Agriculture 2021年第2期20卷 450-459页

作者： lIU Yue-e lI Yu-xin lU tian-fang XING Jin-feng XU tian-jun CAI Wan-tao ZHANG Yong ZHAO Jiuran WANG Rong-huan Beijing Key laboratory of Maize DNA Fingerprinting and Molecular Breeding Maize Research CenterBeijing Academy of Agriculture&Forestry SciencesBeijing 100097P.R.China

Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha^(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)>fertilizer(11.95%)>hybrids(8.19%)>irrigation(4%) for FP to HH, and hybrids(8.94%)>plant density(4.84%)>fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.

关键词： maize yield gap management factors priority hybrid plant density fertilizer irrigation

Effects of icariin on cGMP-specific PDE5 and cAMP-specific PDE4 activities

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Asian Journal of Andrology 2003年第1期5卷 15-18页

作者： ZC Xin EK Kim CS lin WJ liu l tian YM Yuan J Fu Department of Urology the Ist Hospital Peking University Beijing 100034 China Department of life Science Pohang University of Science and Technology Pohang Korea Knuppe Molecular Urology laboratory Department of Urology UCSF USA

Aim: To clarify the mechanism of the therapeutic action of icariin on erectlile dysfunction (ED). Methods: PDE5 was isolated from the human platelet and PDE4 from the rat liver tissue using the FPlC system (Pharmacia, Milton Keynes, UK) and the Mono Q column. The inhibitory effects of icariin on PDE5 and PDE4 activities were investigated by the two-step radioisotope procedure with [3H]-cGMP/[3H]-cAMP. Papaverine served as the control drug. Results: Icariin and papaverine showed dose-dependent inhibitory effects on PDE5 and PDE4 activities. The IC50 of Icariin and papaverine on PDE5 were 0.432 μmol/l and 0.680μmol/l, respectively and those on PDE4, 73.50 μmol/l and 3.07μmol/l, respectively. The potencies of selectivity of icariin and papaverine on PDE5 (PDE4/PDE5 of IC50) were 167.67 times and 4.54 times, respectively. Conclusion: Icariin is a cGMP-specific PDE5 inhibitor that may be developed into an oral effective agent for the treatment of ED.

关键词： icariin PDE5 cGMP penile erection

Progress of Deep Geological Survey Project under the China Geological Survey

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China Geology 2020年第1期3卷 153-172页

作者： Qing-tian lü Jia-yong Yan Xuan-hua Chen He-sheng Hou Wen-shi Wang Yu-le Hu Chinese Academy of Geological Sciences China Geological SurveyMinistry of Natural ResourcesBeijing 100037China SinoProbe Center Chinese Academy of Geological SciencesChina Geological SurveyMinistry of Natural ResourcesBeijing 100037China Institute of Exploration Technique Chinese Academy of Geological SciencesNanchang 330013China China University of Geosciences Wuhan 430074China

Serving as a way to understand the material composition,structure,and dynamic process of the Earth's interior,deep earth exploration is driven by not only mankind's pursuit of natural mysteries but also mankind's basic need to obtain resources and guarantee economic and social *** first phase of deep earth exploration of China(SinoProbe)was carried out from 2008 to 2016 and tremendous results were *** 2016,the China Geological Survey launched a Deep Geological Survey Project(also referred to as the Project)to continuously explore the deep *** on the national energy resources strategy,the Belt and Road Initiative,and major basic issues of the geological survey,the Project was carried out in Songliao Basin(an important energy base in China)and major geological boundaries and tectonic units including Qilian Mountains-tianshan Mountains and Qinzhou-Hangzhou juncture *** purpose of it is to reveal the process,structure,and forming patterns of the deep ore deposits and petroleum reservoirs,clarify the evolutionary pattern and controlling factors of Mesozoic environmental climate,and discover deep fine structures of key orogens,basins,and mountains by comprehensive geophysical exploration and scientific *** achievements have been obtained after more than three years of efforts,including a cumulative 1552 km of deep seismic reflection profiles and magnetotelluric profiles,an ultra-deep continental scientific crilling well,a scientific drilling pilot hole,and a magnetotelluric array and a portable broadband seismic array,both of which cover South ***,significant progress has been made in ultra-deep drilling technology,deep oil and gas discovery in Songliao Basin,and basic geological issues of Qilian Orogen and Qinzhou-Hangzhou juncture belt in South China,greatly accelerating the deep earth exploration in China and further consolidating China's position as a power in deep earth exploration.

关键词： Deep geological survey Deep oil and gas discovery Ultra-deep scientific drilling technology Songke No.2 well Qilian Mountains-tianshan Mountains Qinzhou-Hangzhou juncture belt Songliao Basin China

Difference in the anti-fatigue effect of moxibustion at different acupoints in one-off exhausted rats

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World Journal of Acupuncture-Moxibustion 2019年第4期29卷 279-284页

作者： Xin Wang Ya-hui Zhang Zhi-fang Zhang Shi-ling lǚ Yu-lei liang Dong-yun Sun tian-yuan lǚ School of Acupuncture Moxibustion and TuinaHebei University of Chinese MedicineShijiazhuang 050200China

Objective:To explore the difference in the anti-fatigue effect of moxibustion at different acupoints through observing the impacts of moxibustion at"Shènshù(肾俞Bl23)","Zúsānlǐ(足三里ST36)","Guānyuán(关元CV4)"and"Shénquè(神阙CV8)"on energy metabolic indexes in the one-off exhausted ***:A total of 56 SPF male rats were randomized into 7 groups,named a blank group,a model group,a non-acupoint group,a"Bl23"group,a"ST36"group,a"CV4"group and a"CV8"group,8 rats in each *** one-off exhaustion model was established by weight-bearing swimming *** after the exhaustive swimming of rats in each intervention group,the mild moxibustion was applied at the corresponding acupoints for 15 min immediately.4 h after the exhaustive swimming,the blood was collected from the femoral artery and the quadriceps femoris of the left hindlimb was *** levels of blood lactate(BlD),lactate dehydrogenase(lDH),creatine kinase(CK)and blood urea nitrogen(BUN),the expressions of adenosine triphosphatease(ATP),fructose-6-phosphofructokinase(PFK)and malomdialdehyde(MDA)in the quadriceps femoris and the activity of superoxide dismutase(SOD)and catalase(CAT)were ***:Compared with the model group and the non-acupoint group,the levels of serum BlD,lDH,CK and BUN were all lower those in the"Bl23"group,the"ST36"group,the"CV4"group and the"CV8"group,indicating a statistical significance(all Pl group and the nonacupoint group,PFK was higher in the"Bl23"group,indicating a statistical significance(both Pl group and the non-acupoint group,PFK was higher in the"ST36"group and the"CV4"group,indicating a statistical significance(all Plusion:It was found in the research that moxibustion at"Bl23""ST36""CV4"and"CV8"regulated the energy metabolism in the one-off exhausted rats so as to bring the anti-fatigue effect into play and the effect was different among the *** at"CV8"may work on the preve

关键词： Anti-fatigue Exhaustive exercise Guānyuán(关元CV4) Mild moxibustion Shénquè(神阙CV8) Shènshù(肾俞Bl23) Zúsānlǐ(足三里ST36)

A new recognition algorithm of the lunar mare area basing on the DEM contrast

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A new recognition algorithm of the lunar mare area basing on...

Nanocrystal Model for liquid Metals and Amorphous Metals

The 2015 International Conference on Advanced Materials and Engineering Structural Technology(ICAMEST 2015)

作者： T.l.Xie H.K.Jiang J.l.Wang X.l.tian X.l.tian A.A.Xu Faculty of Information Technology Macau University of Science and Technology lunar and Planetary Science laboratory Space Science InstituteMacau University of Science and Technology

The new algorithm proposed in this paper proved its advantage by identifying the lunar mare area and the non-mare area of the DEM images with the local area *** different testing areas have shown that almost all the accuracy of the new algorithm has been tested and the results are *** corresponding Kappa coefficients of the new algorithm proposed are better than known result offered by the previous algorithm in using both DEM and CCD data.

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Journal of Materials Science & Technology 2010年第1期26卷 69-74页

作者： X.l. tian, C.W. Zhan, J.X. Hou, X.C. Chen and J.J. Sun Key laboratory of liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061, China Key laboratory of liquid Structure and Heredity of Materials Ministry of Education Shandong University Jinan 250061 China

A nanocrystal model for liquid metals and amorphous metals has been developed. With the nanocrystal model, the broadening peak profiles （BPPs） of Cu, Al, Al65Cu20Fe15 alloy, Cu7oNi30 alloy and Fe50Si50 alloy were gained by broadening the X-ray diffraction （XRD） peaks of a crystal lattice. By comparing the BPPs with the XRD intensity curves measured on the liquid metals, it is found that the BPPs are closely in agreement with the XRD intensity curves, respectively, except the FesoSiso alloy. Therefore, the nanocrystal model can be used to determine if the atomic cluster structure of the liquid metal is similar to the structure of its crystal lattice.

关键词： liquid metal Atomic cluster Structure Crystal lattice