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| 1 | Contrasting responses of net primary productivity to inter-annual variability and changes of climate among three forest types in northern China显示文摘Aims A lack of explicit information on differential controls on net primary productivity(NPP)across regions and ecosystem types is largely responsible for uncertainties in global trajectories of terrestrial carbon balance with changing environment.The objectives of this study were to determine how NPP of different forest types would respond to inter-annual variability of climate and to examine the responses of NPP to future climate change scenarios across contrasting forest types in northern China.Methods We investigated inter-annual variations of NPP in relation to climate variability across three forest types in northern China,including a boreal forest dominated by Larix gmelinii Rupr.,and two temperate forests dominated by Pinus tabulaeformis Carr.and Quercus wutaishanica Mayr.,respectively,and studied the responses of NPP in these forests to predicted changes in climate for the periods 2011–40,2041–70 and 2070–100 under carbon emission scenarios A2 and B2 of Intergovernmental Panel on Climate Change.We simulated the responses of NPP to predicted changes in future climate as well as inter-annual variability of the present climate with the Biome-BGC version 4.2 based on site-and species-specific parameters.The modeled forest NPP data were validated against values in literature for similar types of forests and compared with inter-annual growth variations reflected by tree-ring width index(RWI)at the study sites.Important Findings Inter-annual variations in modeled NPP during the period 1960–06 were mostly consistent with the temporal patterns in RWI.There were contrasting responses of modeled NPP among the three forest types to inter-annual variability of the present climate as well as to predicted changes in future climate.The modeled NPP was positively related to annual mean air temperature in the L.gmelinii forest(P<0.001),but negatively in the P.tabulaeformis forest(P=0.05)and the Q.wutaishanica forest(P=0.03),while the relationships of modeled NPP with annual precipitation for the three forest types were all positive.Multiple stepwise regression analyses showed that temperature was a more important constraint of NPP than precipitation in the L.gmelinii forest,whereas precipitation appeared to be a prominent factor limiting the growth in P.tabulaeformis and Q.wutaishanica.Model simulations suggest marked,but differential increases in NPP across the three forest types with predicted changes in future climate. | Shuai Ouyang Xiangping Wang Yulian Wu Osbert Jianxin Sun | 2014 | Journal of Plant Ecology2014，7，3： | 9 |
| 2 | A Remote Sensing-based Analysis on the Impact of Wenchuan Earthquake on the Core Value of World Nature Heritage Sichuan Giant Panda Sanctuary显示文摘In this study,we used remotely sensed data,GIS modeling,and statistical methods to evaluate the damage caused by the Wenchuan Earthquake (May 12,2008) to the giant panda (Ailuropoda melanoleuca) habitat in the World Nature Heritage Sichuan Giant Panda Sanctuary (WHSGPS) in China.A landscape ecological analysis found increases of landscape heterogeneity,complexity,and fragmentation in the giant panda habitat after the earthquake.A terrain analysis found that slope and elevation are directly associated with the distribution of the damaged areas.As slope and elevation increase,the size of the damaged area keeps increase until to a peak,and then starts to drop.The total area of the damaged vegetation in our study area is 114.26 km 2,accounting for 3.78% of the study area;30.46% of that 114.26 km 2 is located in the Core Zone of WHSGPS.There are 18.57km 2 of the damaged vegetation located in the identified suitable giant panda habitat,accounting for 1.75% of the total area of suitable giant panda habitats in the study area.Based on these findings,we conclude that the Wenchuan Earthquake does not have significant impact on the WHSGPS as a whole. | YU Hu ZHAO Yongtao MA Yuewei SUN Yulian ZHANG Hu YANG Shihong LUO Yong | 2011 | Journal of Mountain Science2011，8，3： | 8 |
| 3 | A test of BIOME-BGC with dendrochronology for forests along the altitudinal gradient of Mt. Changbai in northeast China显示文摘Aims Process-based models are basic tools for predicting the response of forest carbon to future climate change.The models have commonly been tested for their predictions of spatial variation in forest produc-tivity,but much less for their ability to predict temporal variation.Here,we explored methods to test the models with tree rings,using BIOME-BGC as an example.Methods We used net primary productivity(NPP)data and tree rings col-lected from five major forest types along the altitudinal gradient of Mt.Changbai,northeast China,to test local-parameterized BIOME-BGC model.We first test the model’s predictions of both spatial(Test 1)and temporal changes(Test 2)in productivity.Then we test if the model can detect the climatic factors limiting forest productiv-ity during historical climate change,as revealed by dendroclimatic analyses(Test 3).Important Findings Our results showed that BIOME-BGC could well simulate NPP of five forest types on Mt.Changbai,with an r^(2) of 0.69 between mod-eled and observed NPP for 17 plots along the altitudinal gradient(Test 1).Meanwhile,modeled NPP and ring-width indices were cor-related and showed similar temporal trends for each forest type(Test 2).While these tests suggest that the model’s predictions on spatial and temporal variation of NPP were acceptable,a further test that relate the correlations of modeled NPP with climate variables to the correlations of ring widths with climate(Test 3)showed that the model did not well identify the climatic factors limiting historical productivity dynamics for some forest types,and thus cannot reli-ably predict their future.Both dendrochronology and BIOME-BGC showed that forest types differed markedly in the climate factors limiting productivity because of differences in tree species and cli-mate condition,and thus differed in responses to climate change.Our results showed that a successful prediction of spatial NPP pat-terns cannot assure that BIOME-BGC can well simulate histori-cal NPP dynamics.Further,a correlation between modeled NPP and tree-ring series cannot assure that the limiting climatic factors for productivity have been correctly identified by the model.Our results suggest the necessity to test the temporal predictions of pro-cess-based models in a more robust way,and further integration of dendrochronology and biogeochemistry modeling may be helpful for this purpose. | Yulian Wu Xiangping Wang Shuai Ouyang Kai Xu Bradford A.Hawkins Osbert Jianxin Sun | 2017 | Journal of Plant Ecology2017，10，3： | 2 |
| 4 | The preparationand characterization of hydrotalcite using for PVC显示文摘 | Sun Yulian Huang Huaizhong Wang Yifan | 2011 | Journal of Huazhong Normal University:Natural Sciences2011，45，3： | 1 |
| 5 | Effect of six-month standardized tertiary rehabilitation program on the activities of daily living in stroke patients with hemiplegia显示文摘BACKGROUND:At present,there are many studies on the rehabilitation therapy of stroke patients with hemiplegia,but there is deficiency of corresponding standardized rehabilitation program. OBJECTIVE:To explore the effects of standardized tertiary rehabilitation on the activities of daily living in stroke patients with hemiplegia within 6 months after attack. DESIGN:A clinical observation. SETTING:Department of Rehabilitation Medicine,Huashan Hospital of Fudan University. PARTICIPANTS:Eighty-two outpatients and inpatients with acute stroke were selected from the Department of Neurology,Shanghai Huashan Hosptial from January 1999 to June 2003,including 49 males and 33 females,40-80 years of age,with a mean age of(65±11) years old. Inclusive criteria:According to the diagnostic standards for cerebrovascular diseases set by Fourth National Academic Meeting for Cerebrovascular Disease in 1995,the patients were diagnosed as new attack of cerebral infarction or cerebral hemorrhage,and confirmed by CT or MRI to be initial patients;They should be accorded with the following conditions,including within 1 week after stabilization of life signs,Glasgow coma score > 8 points,40-80 years of age,with disturbance of limb function. Informed consents were obtained from all the patients or their relatives. Exclusive criteria:Patients were excluded due to active liver disease,liver and kidney malfunction,congestive heart failure,malignant tumor,history of dementia,failure in respiratory function,tetraplegia;cerebral infarction or cerebral hemorrhage for more than 3 weeks;unable to be followed up due to in other cities and provinces;psychiatric history;deafness and muteness. According to the will of the patients or their relatives,the patients who accepted the standardized rehabilitation program were enrolled as the treatment group(n =42),and the others as the control group(n =40). Approval was obtained from the ethical committee of the hospital. METHODS:All the patients were given routine therapies of internal medicine after admission. According to the conditions of Brunnstom recovery 6-phase evaluation,the patients in the treatment group were trained with the pre-designed comprehensive standardized rehabilitation program for corresponding period. At early period(within about 1 month after attack),the patients received rehabilitative interventions in the Department of Emergency or Department of Neurology,once a day,45 minutes for each time,5 times a week;At middle period(about 1-3 months after attack),the patients received rehabilitative interventions in the rehabilitation ward or center,once to twice a day,30-45 minutes for each time,4-5 days a week;At late period(about 3-6 months after attack),the patients received rehabilitative intervention mainly assisted by rehabilitation physician in the community,relatives and volunteers,3-4 times a week,and they were followed in the house or outpatient department once every two weeks. MAIN OUTCOME MEASURES:The patients were evaluated blindly by the same rehabilitation physician using scale of modified Barthel index at admission and 1,3 and 6 months after attack respectively. RESULTS:Totally 82 patients with acute stroke were enrolled,and 3 cases in the treatment group missed,including 2 cases died at 1 month after admission,and 1 case refused the follow up 10 days later,all the others were involved in the analysis of results. The scores of modified Barthel index at corresponding time points after admission in the treatment group were all obviously higher than those in the control group(P < 0.01),and the score differences were also obviously higher than those in the control group(P < 0.01). The activities of daily living at admission and 1,3 and 6 months after admission in the treatment group were 22.50%,46.43%,75.95% and 89.52% of that of normal people respectively,and those in the control group were 17.09%,25.77%,43.38% and 55.00% respectively. The activities of daily living at admission and 1,3 and 6 months in the treatment group were 131.66%,180.17%,175.08% and 162.76% of those in the controlgroup. As compared with at admission,the percentage of the score difference to the total score at the ends of the 1st,3rd and 6th months were 23.93%,53.45% and 67.02% in the treatment group,while 8.67%,25.36% and 36.98% in the control group. CONCLUSION:Standardized tertiary rehabilitation can obviously promote the activities of daily living in stroke patients with hemiplegia. | Yulian Zhu Yongshan Hu Yi Wu Congyu Jiang Wenke Fan Limin Sun Zhen Xie Li Shen BingZhu Yulong Bai | 2007 | Neural Regeneration Research2007，2，11： | 0 |
| 6 | Role of tannin pretreatment in flotation separation of magnesite and dolomite显示文摘Flotation separation of magnesite and its calcium-containing carbonate minerals is a difficult problem.Recently,new regulat-ors have been proposed for magnesite flotation decalcification,although traditional regulators such as tannin,water glass,sodium carbon-ate,and sodium hexametaphosphate are more widely used in industry.However,they are rarely used as the main regulators in research because they perform poorly in magnesite and dolomite single-mineral flotation tests.Inspired by the limonite presedimentation method and the addition of a regulator to magnesite slurry mixing,we used a tannin pretreatment method for separating magnesite and dolomite.Microflotation experiments confirmed that the tannin pretreatment method selectively and largely reduces the flotation recovery rate of dolomite without affecting the flotation recovery rate of magnesite.Moreover,the contact angles of the tannin-pretreated magnesite and dolomite increased and decreased,respectively,in the presence of NaOl.Zeta potential and Fourier transform infrared analyses showed that the tannin pretreatment method efficiently hinders NaOl adsorption on the dolomite surface but does not affect NaOl adsorption on the magnesite surface.X-ray photoelectron spectroscopy and density functional theory calculations confirmed that tannin interacts more strongly with dolomite than with magnesite. | Xiufeng Gong Jin Yao Jun Guo Bin Yang Haoran Sun Wanzhong Yin Yulian Wang Yafeng Fu | 2024 | International Journal of Minerals,Metallurgy and Materials2024，31，3： | 0 |
| 7 | Relaxed Stability Criteria for Time-Delay Systems:A Novel Quadratic Function Convex Approximation Approach显示文摘This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying delays.By introducing two adjustable parameters and two free variables,a novel convex function greater than or equal to the quadratic function is constructed,regardless of the sign of the coefficient in the quadratic term.The developed lemma can also be degenerated into the existing quadratic function negative-determination(QFND)lemma and relaxed QFND lemma respectively,by setting two adjustable parameters and two free variables as some particular values.Moreover,for a linear system with time-varying delays,a relaxed stability criterion is established via our developed lemma,together with the quivalent reciprocal combination technique and the Bessel-Legendre inequality.As a result,the conservatism can be reduced via the proposed approach in the context of constructing Lyapunov-Krasovskii functionals for the stability analysis of linear time-varying delay systems.Finally,the superiority of our results is illustrated through three numerical examples. | Shenquan Wang Wenchengyu Ji Yulian Jiang Yanzheng Zhu Jian Sun | 2024 | IEEE/CAA Journal of Automatica Sinica2024，11，4： | 0 |
| 8 | N-doped graphene anchored ultrasmall Ir nanoparticles as bifunctional electrocatalyst for overall water splitting显示文摘Seeking for extremely active and durable bifunctional electrocatalysts towards the overall water splitting possesses a strategic significance on the development of sustainable and clean energy for the replacement of fossil fuels.Ir-based nanomaterials are deemed as one of the most highefficiency oxygen evolution reaction electrocatalysts while the hydrogen evolution reaction performance is unfavorable.In this work,we report a one-pot hydrothermal synthesis of N-doped graphene anchored Ir nanoparticles(Ir/N-rGO) with ultrasmall particle size(~2.0 nm).Apart from the predictably superior OER performance,the resultant Ir/N-rGO also displays excellent hydrogen evolution reaction(HER) performance,requiring merely 76 and 260 mV overpotentials to achieve the current density of 10 mA cm^(-2) towards HER and OER,respectively.When applied as the bifunctional electrodes for overall water splitting,Ir/N-rGO needs a lower overpotential(1.74 V) to achieve a current density of50 mA cm^(-2) in alkaline solution,exceeding that of Pt/C and RuO_(2) couple(1.85 V).Thus,the as-fabricated Ir/N-rGO has a commendable prospect in the practical application of alkaline water electrocatalysis. | Wenqing Yao Xian Jiang Yulian Li Cuiting Zhao Linfei Ding Dongmei Sun Yawen Tang | 2022 | Green Energy & Environment2022，7，5： | 0 |
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