Application of novel radio technologies and equip-ment inevitably leads to electromagnetic pollution.One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain hi...Application of novel radio technologies and equip-ment inevitably leads to electromagnetic pollution.One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain high-performance microwave absorbers.Herein,we reported a one-dimensional N-doped carbon nanofibers material which encapsulated the hollow Co_(3)SnC_(0.7) nano-cubes in the fiber lumen by electrospinning.Space charge stacking formed between nanoparticles can be channeled by longitudinal fibrous structures.The dielectric constant of the fibers is highly related to the carbonization temperature,and the great impedance matching can be achieved by synergetic effect between Co_(3)SnC_(0.7) and carbon network.At 800℃,the necklace-like Co_(3)SnC_(0.7)/CNF with 5%low load achieves an excellent RL value of−51.2 dB at 2.3 mm and the effective absorption bandwidth of 7.44 GHz with matching thickness of 2.5 mm.The multiple electromagnetic wave(EMW)reflections and interfacial polarization between the fibers and the fibers internal contribute a major effect to attenuating the EMW.These strategies for regulating electromagnetic performance can be expanded to other electromagnetic functional materials which facilitate the development of emerging absorbers.展开更多
Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray method.Meanwhile,pl...Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray method.Meanwhile,plasma activation is developed as a promising strategy to pretreat magnesium surfaces,which facilitates the direct adhesion of coatings with enhanced bonding interfaces.In this work,we engineer the nHA/SF composite coatings with excellent mechanical properties and adhesion force.The optimized parameters of ultrasonic spray bring significant influence on the surface morphologies of coatings.Assisted by hybrid plasma of oxygen and nitrogen(i.e.,O_(2)/N_(2) plasma),the activated Mg-Zn-Ca surfaces are uniformly covered by a robust and compact nHA/SF composite coating,establishing a multifunctional system with superior corrosion resistance and biological performance.Interestingly,secondary oxygen plasma treatment of nHA/SF coatings(A-nHA/SF)promotes the hydrophilicity,leading to a rapid self-repair effect from surface damage.The improvement of anti-corrosion and self-repair provides a dependable platform for better cell adhesion,proliferation,spreading and differentiation.These favorable factors contribute to the preferable in vivo biocompatibility and the promotion of newly formed bones for the A-nHA/SF-coated Mg implants.This study lays important foundations for coating strategy on biomedical magnesium alloy as multifunctional osteogenic system in bioactive implantable applications.展开更多
Background: Pyrroloquinoline quinone(PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of t...Background: Pyrroloquinoline quinone(PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of this study was to investigate the effects of pyrroloquinoline quinone disodium(PQQ·Na2) on reproductive performance in sows.Results: Dietary supplementation with PQQ·Na2 significantly increased the total number of piglets born, the number of piglets born alive and the born alive litter weight. It also increased the antioxidant status in the placenta, plasma and milk. The concentration of NO was significantly increased in the plasma and placenta. RNA-seq analysis showed that462 unigenes were differentially expressed between the control(Con) treatment and PQQ treatment groups.Among these unigenes, 199 were upregulated, while 263 unigenes were downregulated. The assigned functions of the unigenes covered a broad range of GO categories. Reproduction(27, 7.03%) and the reproduction process(27, 7.03%) were assigned to the biological process category. By matching DEGs to the KEGG database, we identified 29 pathways.Conclusions: In conclusion, dietary supplementation with PQQ·Na2 in gestating and lactating sows had positive effects on their reproductive performance.展开更多
To expand the future clinic applications of biodegradable magnesium alloy,polymer coatings with excellent biocompatibility are the keys to solve the local alkalinity and rapid hydrogen release.Natural-organic silk fib...To expand the future clinic applications of biodegradable magnesium alloy,polymer coatings with excellent biocompatibility are the keys to solve the local alkalinity and rapid hydrogen release.Natural-organic silk fibroin provides an approach to fabricate a protective coating on biomedical Mg-Zn-Ca alloy,however,the adhesion force and mechanical properties of the coating on substrates are ought to be further improved without any chemical conversion/intermediate layer.Hereby,based on VUV/O;surface activation,a hybrid of silk fibroin and sodium alginate is proposed to enhance the adhesion force and mechanical properties of the composite coatings on hydrophilic Mg-Zn-Ca alloy surfaces.Various mass ratios of sodium alginate addition were investigated to achieve the optimum coating strategy.The nanoscratch test and nanoindentation test confirmed that the adhesion force was tripled and mechanical properties index was significantly improved when the mass ratio of silk fibroin/sodium alginate was 70/30 compared to pure silk fibroin or sodium alginate coatings.Meanwhile,the corrosion rate of the coated Mg-Zn-Ca alloy was significantly delayed with the addition of sodium alginate,resulting in a reaction layer during corrosion process.Furthermore,the mechanisms for both adhesion and corrosion processes were discussed in detail.Our findings offer more possibilities for the controllable surface performance of degradable metals.展开更多
Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance a...Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance and conductivity of the electrodes.Therefore,highly purified Cu NWs without oxidation are vital for high-performance FTEs.Herein,a facile and effective purification process is introduced to purify Cu NWs in a water and n-hexane system,which takes advantage of the differences in hydrophilicity between Cu NWs and Cu NPs caused by their different adsorption affinities to octadecylamine(ODA).At the same sheet resistance,the transmittance of the purified Cu NW-based FTEs improved approximately 2%compared to that of non-purified Cu NW-based FTEs.Immersion of the electrode in glacial acetic acid removed the surface organics and oxides.After only 40 s of treatment,the sheet resistance dramatically decreased from 10^5 Ohm/sq to 31 Ohm/sq with a transmittance of 85%.In addition,the Cu NW-based FTE conductors showed excellent flexibility(remaining stable after 1000 bending cycles).The Cu NW-based FTEs were further applied to fabricate a flexible transparent heater.At a voltage of 10 V,the temperature of the heater reached 73℃,demonstrating the potential applications of this material in various fields.展开更多
This study aimed to explore an analysis method for baicalin in Scutellaria baicalensis Georgi and make a reference for the analysis of the medicinal value of S. baicalensis cultivated in Jizhou District. The content o...This study aimed to explore an analysis method for baicalin in Scutellaria baicalensis Georgi and make a reference for the analysis of the medicinal value of S. baicalensis cultivated in Jizhou District. The content of baicalin in S. baicalensis cultivated in Jizhou District was determined using high-performance liquid chromatography( HPLC) to judge whether it met the requirements of Chinese Pharmacopoeia; and according to the requirements of the Chinese Pharmacopoeia of 2015 edition,the contents of heavy metals were determined by ICP-MS. The results showed that the contents of baicalin,Cr,Cu,As,Cd and Pb in S. baicalensis planted in Jizhou District were 14. 625 05%,11. 360,12. 830,0. 062 315,0. 025 715 and 0. 176 65 μg/g,respectively. The content of baicalin in S. baicalensis planted in Jizhou District was much higher than the standard( ≥ 9. 0%) of Chinese Pharmacopoeia of 2015 edition,and the contents of heavy metals were also below the limit( ≤20/1000 000) required by Chinese Pharmacopoeia of 2015 edition.展开更多
Focusing on the role of initial condition uncertainty,we use WRF initial perturbation ensemble forecasts to investigate the uncertainty in intensity forecasts of Tropical Cyclone(TC)Rammasun(1409),which is the stronge...Focusing on the role of initial condition uncertainty,we use WRF initial perturbation ensemble forecasts to investigate the uncertainty in intensity forecasts of Tropical Cyclone(TC)Rammasun(1409),which is the strongest TC to have made landfall in China during the past 50 years.Forecast results indicate that initial condition uncertainty leads to TC forecast uncertainty,particularly for TC intensity.This uncertainty increases with forecast time,with a more rapid and significant increase after 24 h.The predicted TC develops slowly before 24 h,and at this stage the TC in the member forecasting the strongest final TC is not the strongest among all members.However,after 24 h,the TC in this member strengthens much more than that the TC in other members.The variations in convective instability,precipitation,surface upward heat flux,and surface upward water vapor flux show similar characteristics to the variation in TC intensity,and there is a strong correlation between TC intensity and both the surface upward heat flux and the surface upward water vapor flux.The initial condition differences that result in the maximum intensity difference are smaller than the errors in the analysis system.Differences in initial humidity,and to a lesser extent initial temperature differences,at the surface and at lower heights are the key factors leading to differences in the forecasted TC intensity.These differences in initial humidity and temperature relate to both the overall values and distribution of these parameters.展开更多
In recent years,under the stimulation of the national policy and the land circulation policy,the villages and towns have begun to guide the farmers to carry on the land circulation in an orderly way,combine the target...In recent years,under the stimulation of the national policy and the land circulation policy,the villages and towns have begun to guide the farmers to carry on the land circulation in an orderly way,combine the targeted poverty alleviation with the development of modern agriculture,and drive the registered households to participate in the modern agricultural industry and achieve the goal of getting rid of poverty and getting rich while realizing the transformation and upgrading of agriculture. The transfer of land management right can drive the local employment and the poverty reduction through industrial development is implemented. Taking Mopi Village in Xinping County as an example,this paper analyzes the main methods and effects of the transfer of land management right in this village in promoting poverty reduction through industrial development,and puts forward the existing problems and suggestions.展开更多
[Objectives] This study aimed to evaluate the quality of Salvia miltiorrhiza cultivated in Jizhou. [Methods] The contents of chemical ingredients( tanshinone ⅡA,tanshinone Ⅰ and salvianolic acid B) in S. miltiorrhiz...[Objectives] This study aimed to evaluate the quality of Salvia miltiorrhiza cultivated in Jizhou. [Methods] The contents of chemical ingredients( tanshinone ⅡA,tanshinone Ⅰ and salvianolic acid B) in S. miltiorrhiza were determined by high-performance liquid chromatography( HPLC),and the chemical composition of S. miltiorrhiza planted in Jizhou and purchased from market was compared.[Results]The contents of tanshinone ⅡA,tanshinone I and salvianolic acid B in S. miltiorrhiza planted in Jizhou were 0. 014%,0. 421 2%and 3. 018%,respectively,higher than the standards of the Chinese Pharmacopoeia of the 2015 edition. [Conclusions]The chemical composition of S. miltiorrhiza planted in Jizhou meets the standards of the Chinese Pharmacopoeia of the 2015 edition.展开更多
[Objectives]To enrich the species resources of Tianjin,Aornia melanocarpa was introduced and cultivated in 4 districts of Tianjin.[Methods]Two consecutive years of observation in 2018-2019 and research on the phenolog...[Objectives]To enrich the species resources of Tianjin,Aornia melanocarpa was introduced and cultivated in 4 districts of Tianjin.[Methods]Two consecutive years of observation in 2018-2019 and research on the phenological period,high yield and fruit economic traits in 4 districts of Tianjin were carried out.[Results]The A.melanocarpa of the Linhai Jiayuan Experimental Site in Jinghai District has larger single fruit weight,higher nutrient composition,stronger plant growth,higher yield and storage stability,so this site can be used as a main planting base for large-scale planting of A.melanocarpa;the experimental site of Tianjin Agricultural University East Campus and the experimental site of Cuiping Lake Science Park of Jizhou District have a sour and astringent taste but relatively low yield,need to be processed as by-products in combination with market prices to determine whether to plant;the experimental site of Tianjin Agricultural University West Campus has low yield,small fruit and poor taste,and the planting effect is the worst among the four experimental sites.[Conclusions]From the overall economic traits of fruits,the fruits produced in the experimental site of Jinghai District have sufficient weight,high solid-acid ratio,and relatively high nutrient content,thus this experimental site can be used as large-scale cultivation base for A.melanocarpa.展开更多
With seeds as experimental materials,MS was used as the basic medium to combine different species and concentrations of auxin and mitogen for proliferation,elongation and rooting culture. The best combination of mediu...With seeds as experimental materials,MS was used as the basic medium to combine different species and concentrations of auxin and mitogen for proliferation,elongation and rooting culture. The best combination of medium and the most suitable medium were selected. The results showed that the best formula for the medium was MS + 0. 5 mg/L BA + 0. 5 mg/L IAA + 30 g/L sucrose in the proliferation culture,MS + 0. 25 mg/L BA + 0. 5 mg/L IAA + 30 g/L sucrose in the elongation culture,and MS + 0. 5 mg/L IAA + 20 g/L sucrose in the rooting culture respectively. The experimental results will be applied in the rapid propagation and breeding of high-quality seedlings of Platycodon grandiflorus.展开更多
The contents of chlorogenic acid and luteoloside in Flos Lonicerae from Binhai New Area and Jinnan District of Tianjin were determined to provide basis for the quality identification of this medicinal material. The co...The contents of chlorogenic acid and luteoloside in Flos Lonicerae from Binhai New Area and Jinnan District of Tianjin were determined to provide basis for the quality identification of this medicinal material. The content of chlorogenic acid was determined by HPLC. In Flos Lonicerae from Binhai New Area and in Flos Lonicerae harvested at different stages from Jinnan District,the contents of chlorogenic acid were 3. 804%,5. 507%( three green stage),4. 855%( silver flower stage) and 4. 220%( golden flower stage),respectively,and the contents of luteoloside were 5. 53%,12. 405%( three green stage),14. 370%( silver flower stage) and 0. 917%( golden flower stage),respectively. The contents of chlorogenic acid in Flos Lonicerae from Jinnan District were higher than that from Binhai New Area. Among different stages,the content of chlorogenic acid was highest in three green stage,followed by that in silver flower stage. As the flowers bloomed,the content of chlorogenic acid in the medicinal material showed a significant downward trend. In Flos Lonicerae from Jinnan District,the content of luteoloside was highest in silver flower stage and lowest in golden flower stage.展开更多
Systemic lupus erythematosus(SLE),a severe autoimmune disorder,is characterized by systemic inflammatory response,autoantibody accumulation and damage to organs.The dysregulation of double-negative(DN)T cells is consi...Systemic lupus erythematosus(SLE),a severe autoimmune disorder,is characterized by systemic inflammatory response,autoantibody accumulation and damage to organs.The dysregulation of double-negative(DN)T cells is considered as a crucial commander during SLE.Neddylation,a significant type of protein post-translational modification(PTM),has been well-proved to regulate T cell-mediated immune response.However,the function of neddylation in SLE is still unknown.Here,we reported that neddylation inactivation with MLN4924,a specific inhibitor of NEDD8-activating enzyme E1(NAE1),or genetic abrogation of Ube2m in T cells decreased DN T cell accumulation and attenuated murine lupus development.Further investigations revealed that inactivation of neddylation blocked Bim ubiquitination degradation and maintained Bim level in DN T cells,contributing to the apoptosis of the accumulated DN T cells in lupus mice.Then double knockout(KO)lupus-prone mice(Ube2m-/-Bim-/-lpr)were generated and results showed that loss of Bim reduced Ube2m deficiency-induced apoptosis in DN T cells and reversed the alleviated lupus progression.Our findings identified that neddylation inactivation promoted Bim-mediated DN T cell apoptosis and attenuated lupus progression.Clinically,we also found that in SLE patients,the proportion of DN T cells was raised and their apoptosis was reduced.Moreover,compared to healthy groups,SLE patients exhibited decreased Bim levels and elevated Cullin1 neddylation levels.Meantime,the inhibition of neddylation induced Bim-dependent apoptosis of DN T cells isolated from SLE patients.Altogether,our findings provide the direct evidence about the function of neddylation during lupus,suggesting a promising therapeutic approach for this disease.展开更多
Reactive power optimization of distribution networks is traditionally addressed by physical model based methods,which often lead to locally optimal solutions and require heavy online inference time consumption.To impr...Reactive power optimization of distribution networks is traditionally addressed by physical model based methods,which often lead to locally optimal solutions and require heavy online inference time consumption.To improve the quality of the solution and reduce the inference time burden,this paper proposes a new graph attention networks based method to directly map the complex nonlinear relationship between graphs(topology and power loads)and reactive power scheduling schemes of distribution networks,from a data-driven perspective.The graph attention network is tailored specifically to this problem and incorporates several innovative features such as a self-loop in the adjacency matrix,a customized loss function,and the use of max-pooling layers.Additionally,a rulebased strategy is proposed to adjust infeasible solutions that violate constraints.Simulation results on multiple distribution networks demonstrate that the proposed method outperforms other machine learning based methods in terms of the solution quality and robustness to varying load conditions.Moreover,its online inference time is significantly faster than traditional physical model based methods,particularly for large-scale distribution networks.展开更多
The complexity and uncertainty in power systems cause great challenges to controlling power grids.As a popular data-driven technique,deep reinforcement learning(DRL)attracts attention in the control of power grids.How...The complexity and uncertainty in power systems cause great challenges to controlling power grids.As a popular data-driven technique,deep reinforcement learning(DRL)attracts attention in the control of power grids.However,DRL has some inherent drawbacks in terms of data efficiency and explainability.This paper presents a novel hierarchical task planning(HTP)approach,bridging planning and DRL,to the task of power line flow regulation.First,we introduce a threelevel task hierarchy to model the task and model the sequence of task units on each level as a task planning-Markov decision processes(TP-MDPs).Second,we model the task as a sequential decision-making problem and introduce a higher planner and a lower planner in HTP to handle different levels of task units.In addition,we introduce a two-layer knowledge graph that can update dynamically during the planning procedure to assist HTP.Experimental results conducted on the IEEE 118-bus and IEEE 300-bus systems demonstrate our HTP approach outperforms proximal policy optimization,a state-of-the-art deep reinforcement learning(DRL)approach,improving efficiency by 26.16%and 6.86%on both systems.展开更多
1.Introduction During massive data movements in digital computing systems,several issues have emerged such as high latency,energy ineffi-ciency,and low bandwidth due to the physical separation of pro-cessor and memory...1.Introduction During massive data movements in digital computing systems,several issues have emerged such as high latency,energy ineffi-ciency,and low bandwidth due to the physical separation of pro-cessor and memory units(so-called memory wall)[1-3].To miti-gate the data-movement limitations,three-dimensional(3D)chip integration becomes an optimal solution within von Neumann ar-chitecture since the dense vertical interconnections shorten the distance between chips[4,5].However,the extensively used micro solder bumps for 3D chip stacking impede the further improve-ment of interconnection pitch(<10μm).In this scenario,the Cu/SiO_(2) hybrid bonding technology came into being.Owing to the coexistence of planarized Cu connections and SiO_(2) layers,Cu/SiO_(2) hybrid bonding is the desirable enabler of submicron ultra-dense integration(<1μm),which benefits from Cu-Cu and SiO_(2)-SiO_(2) homogeneous direct bonding replacing micro bumps and underfill[6,7].展开更多
基金supported by the National Natural Science Foundation of China(72293573,72104226)the Research Topic of Securities Futures Industry Standard(BZKT-2022-041)Anhui Province 2022 Annual New Era Education Quality Project(Postgraduate Education)(2022zyxwjxalk003).
基金financially supported by the Natural Science Foundation of Shandong Province (No. ZR2019YQ24)Taishan Scholars and Young Experts Program of Shandong Province (No.tsqn202103057)+1 种基金the Qingchuang Talents Induction Program of Shandong Higher Education Institution (Research and Innovation Team of Structural-Functional Polymer Composites)Special Financial of Shandong Province (Structural Design of High-efficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Talent Teams)
文摘Application of novel radio technologies and equip-ment inevitably leads to electromagnetic pollution.One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain high-performance microwave absorbers.Herein,we reported a one-dimensional N-doped carbon nanofibers material which encapsulated the hollow Co_(3)SnC_(0.7) nano-cubes in the fiber lumen by electrospinning.Space charge stacking formed between nanoparticles can be channeled by longitudinal fibrous structures.The dielectric constant of the fibers is highly related to the carbonization temperature,and the great impedance matching can be achieved by synergetic effect between Co_(3)SnC_(0.7) and carbon network.At 800℃,the necklace-like Co_(3)SnC_(0.7)/CNF with 5%low load achieves an excellent RL value of−51.2 dB at 2.3 mm and the effective absorption bandwidth of 7.44 GHz with matching thickness of 2.5 mm.The multiple electromagnetic wave(EMW)reflections and interfacial polarization between the fibers and the fibers internal contribute a major effect to attenuating the EMW.These strategies for regulating electromagnetic performance can be expanded to other electromagnetic functional materials which facilitate the development of emerging absorbers.
基金supported by the National Natural Science Foundation of China(Grant No.51975151)the Heilongjiang Provincial Natural Science Foundation of China(Grant No.LH2019E041)the Heilongjiang Touyan Team.
文摘Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray method.Meanwhile,plasma activation is developed as a promising strategy to pretreat magnesium surfaces,which facilitates the direct adhesion of coatings with enhanced bonding interfaces.In this work,we engineer the nHA/SF composite coatings with excellent mechanical properties and adhesion force.The optimized parameters of ultrasonic spray bring significant influence on the surface morphologies of coatings.Assisted by hybrid plasma of oxygen and nitrogen(i.e.,O_(2)/N_(2) plasma),the activated Mg-Zn-Ca surfaces are uniformly covered by a robust and compact nHA/SF composite coating,establishing a multifunctional system with superior corrosion resistance and biological performance.Interestingly,secondary oxygen plasma treatment of nHA/SF coatings(A-nHA/SF)promotes the hydrophilicity,leading to a rapid self-repair effect from surface damage.The improvement of anti-corrosion and self-repair provides a dependable platform for better cell adhesion,proliferation,spreading and differentiation.These favorable factors contribute to the preferable in vivo biocompatibility and the promotion of newly formed bones for the A-nHA/SF-coated Mg implants.This study lays important foundations for coating strategy on biomedical magnesium alloy as multifunctional osteogenic system in bioactive implantable applications.
基金supported by the National Key Research and Development Plan of China(2016YFD0501207)the China Agriculture Research System(CARS-36)
文摘Background: Pyrroloquinoline quinone(PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of this study was to investigate the effects of pyrroloquinoline quinone disodium(PQQ·Na2) on reproductive performance in sows.Results: Dietary supplementation with PQQ·Na2 significantly increased the total number of piglets born, the number of piglets born alive and the born alive litter weight. It also increased the antioxidant status in the placenta, plasma and milk. The concentration of NO was significantly increased in the plasma and placenta. RNA-seq analysis showed that462 unigenes were differentially expressed between the control(Con) treatment and PQQ treatment groups.Among these unigenes, 199 were upregulated, while 263 unigenes were downregulated. The assigned functions of the unigenes covered a broad range of GO categories. Reproduction(27, 7.03%) and the reproduction process(27, 7.03%) were assigned to the biological process category. By matching DEGs to the KEGG database, we identified 29 pathways.Conclusions: In conclusion, dietary supplementation with PQQ·Na2 in gestating and lactating sows had positive effects on their reproductive performance.
基金supported by the National Natural Science Foundation of China(Grant No.51975151)the China Postdoctoral Science Foundation(Grant No.2017M610207)+1 种基金the Heilongjiang Provincial Natural Science Foundation of China(Grant No.LH2019E041)the Fundamental Research Funds for Central Universities(Grant No.HIT.NSRIF.2019005)。
文摘To expand the future clinic applications of biodegradable magnesium alloy,polymer coatings with excellent biocompatibility are the keys to solve the local alkalinity and rapid hydrogen release.Natural-organic silk fibroin provides an approach to fabricate a protective coating on biomedical Mg-Zn-Ca alloy,however,the adhesion force and mechanical properties of the coating on substrates are ought to be further improved without any chemical conversion/intermediate layer.Hereby,based on VUV/O;surface activation,a hybrid of silk fibroin and sodium alginate is proposed to enhance the adhesion force and mechanical properties of the composite coatings on hydrophilic Mg-Zn-Ca alloy surfaces.Various mass ratios of sodium alginate addition were investigated to achieve the optimum coating strategy.The nanoscratch test and nanoindentation test confirmed that the adhesion force was tripled and mechanical properties index was significantly improved when the mass ratio of silk fibroin/sodium alginate was 70/30 compared to pure silk fibroin or sodium alginate coatings.Meanwhile,the corrosion rate of the coated Mg-Zn-Ca alloy was significantly delayed with the addition of sodium alginate,resulting in a reaction layer during corrosion process.Furthermore,the mechanisms for both adhesion and corrosion processes were discussed in detail.Our findings offer more possibilities for the controllable surface performance of degradable metals.
基金the National Natural Science Foundation of China(Grant No.51522503)the Program for New Century Excellent Talents in University(NCET-13-0175).
文摘Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance and conductivity of the electrodes.Therefore,highly purified Cu NWs without oxidation are vital for high-performance FTEs.Herein,a facile and effective purification process is introduced to purify Cu NWs in a water and n-hexane system,which takes advantage of the differences in hydrophilicity between Cu NWs and Cu NPs caused by their different adsorption affinities to octadecylamine(ODA).At the same sheet resistance,the transmittance of the purified Cu NW-based FTEs improved approximately 2%compared to that of non-purified Cu NW-based FTEs.Immersion of the electrode in glacial acetic acid removed the surface organics and oxides.After only 40 s of treatment,the sheet resistance dramatically decreased from 10^5 Ohm/sq to 31 Ohm/sq with a transmittance of 85%.In addition,the Cu NW-based FTE conductors showed excellent flexibility(remaining stable after 1000 bending cycles).The Cu NW-based FTEs were further applied to fabricate a flexible transparent heater.At a voltage of 10 V,the temperature of the heater reached 73℃,demonstrating the potential applications of this material in various fields.
基金Supported by Tianjin Science and Technology Plan Project(16PTZSTG-00020)Talents Project of Tianjin Agricultural University.Tianjin Science and Technology Plan Project(17JCYBJC29800)Various Talent Funding Project of Tianjin Agricultural University(J01009030702)
文摘This study aimed to explore an analysis method for baicalin in Scutellaria baicalensis Georgi and make a reference for the analysis of the medicinal value of S. baicalensis cultivated in Jizhou District. The content of baicalin in S. baicalensis cultivated in Jizhou District was determined using high-performance liquid chromatography( HPLC) to judge whether it met the requirements of Chinese Pharmacopoeia; and according to the requirements of the Chinese Pharmacopoeia of 2015 edition,the contents of heavy metals were determined by ICP-MS. The results showed that the contents of baicalin,Cr,Cu,As,Cd and Pb in S. baicalensis planted in Jizhou District were 14. 625 05%,11. 360,12. 830,0. 062 315,0. 025 715 and 0. 176 65 μg/g,respectively. The content of baicalin in S. baicalensis planted in Jizhou District was much higher than the standard( ≥ 9. 0%) of Chinese Pharmacopoeia of 2015 edition,and the contents of heavy metals were also below the limit( ≤20/1000 000) required by Chinese Pharmacopoeia of 2015 edition.
基金financial support from the National Natural Science Foundation of China (Grant Nos. 41575108 and 41475082)
文摘Focusing on the role of initial condition uncertainty,we use WRF initial perturbation ensemble forecasts to investigate the uncertainty in intensity forecasts of Tropical Cyclone(TC)Rammasun(1409),which is the strongest TC to have made landfall in China during the past 50 years.Forecast results indicate that initial condition uncertainty leads to TC forecast uncertainty,particularly for TC intensity.This uncertainty increases with forecast time,with a more rapid and significant increase after 24 h.The predicted TC develops slowly before 24 h,and at this stage the TC in the member forecasting the strongest final TC is not the strongest among all members.However,after 24 h,the TC in this member strengthens much more than that the TC in other members.The variations in convective instability,precipitation,surface upward heat flux,and surface upward water vapor flux show similar characteristics to the variation in TC intensity,and there is a strong correlation between TC intensity and both the surface upward heat flux and the surface upward water vapor flux.The initial condition differences that result in the maximum intensity difference are smaller than the errors in the analysis system.Differences in initial humidity,and to a lesser extent initial temperature differences,at the surface and at lower heights are the key factors leading to differences in the forecasted TC intensity.These differences in initial humidity and temperature relate to both the overall values and distribution of these parameters.
文摘In recent years,under the stimulation of the national policy and the land circulation policy,the villages and towns have begun to guide the farmers to carry on the land circulation in an orderly way,combine the targeted poverty alleviation with the development of modern agriculture,and drive the registered households to participate in the modern agricultural industry and achieve the goal of getting rid of poverty and getting rich while realizing the transformation and upgrading of agriculture. The transfer of land management right can drive the local employment and the poverty reduction through industrial development is implemented. Taking Mopi Village in Xinping County as an example,this paper analyzes the main methods and effects of the transfer of land management right in this village in promoting poverty reduction through industrial development,and puts forward the existing problems and suggestions.
基金Supported by Tianjin Science and Technology Plan Funding Project(16PTZSTG00020)
文摘[Objectives] This study aimed to evaluate the quality of Salvia miltiorrhiza cultivated in Jizhou. [Methods] The contents of chemical ingredients( tanshinone ⅡA,tanshinone Ⅰ and salvianolic acid B) in S. miltiorrhiza were determined by high-performance liquid chromatography( HPLC),and the chemical composition of S. miltiorrhiza planted in Jizhou and purchased from market was compared.[Results]The contents of tanshinone ⅡA,tanshinone I and salvianolic acid B in S. miltiorrhiza planted in Jizhou were 0. 014%,0. 421 2%and 3. 018%,respectively,higher than the standards of the Chinese Pharmacopoeia of the 2015 edition. [Conclusions]The chemical composition of S. miltiorrhiza planted in Jizhou meets the standards of the Chinese Pharmacopoeia of the 2015 edition.
基金Science and Technology Planning Project of Tianjin(17JCYBJC29800&16PTZSTG00020)Science and Technology Planning Project of Jinnan District of Tianjin(201802055)+1 种基金Science and Technology Planning Project of Binhai New Area of Tianjin(BHXQKJXM-SF-2018-33)Graduate Innovation Cultivation Project of Tianjin Agricultural University(2017YPY007).
文摘[Objectives]To enrich the species resources of Tianjin,Aornia melanocarpa was introduced and cultivated in 4 districts of Tianjin.[Methods]Two consecutive years of observation in 2018-2019 and research on the phenological period,high yield and fruit economic traits in 4 districts of Tianjin were carried out.[Results]The A.melanocarpa of the Linhai Jiayuan Experimental Site in Jinghai District has larger single fruit weight,higher nutrient composition,stronger plant growth,higher yield and storage stability,so this site can be used as a main planting base for large-scale planting of A.melanocarpa;the experimental site of Tianjin Agricultural University East Campus and the experimental site of Cuiping Lake Science Park of Jizhou District have a sour and astringent taste but relatively low yield,need to be processed as by-products in combination with market prices to determine whether to plant;the experimental site of Tianjin Agricultural University West Campus has low yield,small fruit and poor taste,and the planting effect is the worst among the four experimental sites.[Conclusions]From the overall economic traits of fruits,the fruits produced in the experimental site of Jinghai District have sufficient weight,high solid-acid ratio,and relatively high nutrient content,thus this experimental site can be used as large-scale cultivation base for A.melanocarpa.
基金Supported by Science and Technology Planning Project of Tianjin City,China(17JCYBJC29800,16PTZSTG00020)
文摘With seeds as experimental materials,MS was used as the basic medium to combine different species and concentrations of auxin and mitogen for proliferation,elongation and rooting culture. The best combination of medium and the most suitable medium were selected. The results showed that the best formula for the medium was MS + 0. 5 mg/L BA + 0. 5 mg/L IAA + 30 g/L sucrose in the proliferation culture,MS + 0. 25 mg/L BA + 0. 5 mg/L IAA + 30 g/L sucrose in the elongation culture,and MS + 0. 5 mg/L IAA + 20 g/L sucrose in the rooting culture respectively. The experimental results will be applied in the rapid propagation and breeding of high-quality seedlings of Platycodon grandiflorus.
基金Supported by Tianjin Science and Technology Plan Project(18YFSDZC00020,17JCYBJC29800,16PTZSTG00020)Science and Technology Plan Project of Jinnan District,Tianjin City(201802055)+2 种基金Science and Technology Project of Binhai New Area,Tianjin City(BHXQKJXM-SF-2018-33)Graduate Innovation Training Program of Tianjin Agricultural University(2017YPY007)College Students'Innovative Entrepreneurial Training Program of Tianjin City(201910061059).
文摘The contents of chlorogenic acid and luteoloside in Flos Lonicerae from Binhai New Area and Jinnan District of Tianjin were determined to provide basis for the quality identification of this medicinal material. The content of chlorogenic acid was determined by HPLC. In Flos Lonicerae from Binhai New Area and in Flos Lonicerae harvested at different stages from Jinnan District,the contents of chlorogenic acid were 3. 804%,5. 507%( three green stage),4. 855%( silver flower stage) and 4. 220%( golden flower stage),respectively,and the contents of luteoloside were 5. 53%,12. 405%( three green stage),14. 370%( silver flower stage) and 0. 917%( golden flower stage),respectively. The contents of chlorogenic acid in Flos Lonicerae from Jinnan District were higher than that from Binhai New Area. Among different stages,the content of chlorogenic acid was highest in three green stage,followed by that in silver flower stage. As the flowers bloomed,the content of chlorogenic acid in the medicinal material showed a significant downward trend. In Flos Lonicerae from Jinnan District,the content of luteoloside was highest in silver flower stage and lowest in golden flower stage.
基金supported by Regional Innovation and Development Joint Fund of the National Foundation of China(U21A20402)to C.W.National Natural Science Foundation of China(No.82074375)+2 种基金the Research Project of Zhejiang Chinese Medical University(No.2023JKZDZC01)to Y.Z.Chongqing International Institute for Immunology(2020YJC10)to L.L.National Natural Science Foundation of China(No.82074217)to Z.H.
文摘Systemic lupus erythematosus(SLE),a severe autoimmune disorder,is characterized by systemic inflammatory response,autoantibody accumulation and damage to organs.The dysregulation of double-negative(DN)T cells is considered as a crucial commander during SLE.Neddylation,a significant type of protein post-translational modification(PTM),has been well-proved to regulate T cell-mediated immune response.However,the function of neddylation in SLE is still unknown.Here,we reported that neddylation inactivation with MLN4924,a specific inhibitor of NEDD8-activating enzyme E1(NAE1),or genetic abrogation of Ube2m in T cells decreased DN T cell accumulation and attenuated murine lupus development.Further investigations revealed that inactivation of neddylation blocked Bim ubiquitination degradation and maintained Bim level in DN T cells,contributing to the apoptosis of the accumulated DN T cells in lupus mice.Then double knockout(KO)lupus-prone mice(Ube2m-/-Bim-/-lpr)were generated and results showed that loss of Bim reduced Ube2m deficiency-induced apoptosis in DN T cells and reversed the alleviated lupus progression.Our findings identified that neddylation inactivation promoted Bim-mediated DN T cell apoptosis and attenuated lupus progression.Clinically,we also found that in SLE patients,the proportion of DN T cells was raised and their apoptosis was reduced.Moreover,compared to healthy groups,SLE patients exhibited decreased Bim levels and elevated Cullin1 neddylation levels.Meantime,the inhibition of neddylation induced Bim-dependent apoptosis of DN T cells isolated from SLE patients.Altogether,our findings provide the direct evidence about the function of neddylation during lupus,suggesting a promising therapeutic approach for this disease.
文摘Reactive power optimization of distribution networks is traditionally addressed by physical model based methods,which often lead to locally optimal solutions and require heavy online inference time consumption.To improve the quality of the solution and reduce the inference time burden,this paper proposes a new graph attention networks based method to directly map the complex nonlinear relationship between graphs(topology and power loads)and reactive power scheduling schemes of distribution networks,from a data-driven perspective.The graph attention network is tailored specifically to this problem and incorporates several innovative features such as a self-loop in the adjacency matrix,a customized loss function,and the use of max-pooling layers.Additionally,a rulebased strategy is proposed to adjust infeasible solutions that violate constraints.Simulation results on multiple distribution networks demonstrate that the proposed method outperforms other machine learning based methods in terms of the solution quality and robustness to varying load conditions.Moreover,its online inference time is significantly faster than traditional physical model based methods,particularly for large-scale distribution networks.
基金supported in part by the National Key R&D Program(2018AAA0101501)of Chinathe science and technology project of SGCC(State Grid Corporation of China).
文摘The complexity and uncertainty in power systems cause great challenges to controlling power grids.As a popular data-driven technique,deep reinforcement learning(DRL)attracts attention in the control of power grids.However,DRL has some inherent drawbacks in terms of data efficiency and explainability.This paper presents a novel hierarchical task planning(HTP)approach,bridging planning and DRL,to the task of power line flow regulation.First,we introduce a threelevel task hierarchy to model the task and model the sequence of task units on each level as a task planning-Markov decision processes(TP-MDPs).Second,we model the task as a sequential decision-making problem and introduce a higher planner and a lower planner in HTP to handle different levels of task units.In addition,we introduce a two-layer knowledge graph that can update dynamically during the planning procedure to assist HTP.Experimental results conducted on the IEEE 118-bus and IEEE 300-bus systems demonstrate our HTP approach outperforms proximal policy optimization,a state-of-the-art deep reinforcement learning(DRL)approach,improving efficiency by 26.16%and 6.86%on both systems.
基金financially supported by the National Natural Science Foundation of China(Nos.92164105 and 51975151)the Heilongjiang Provincial Natural Science Foundation of China(No.LH2019E041)the Heilongjiang Touyan Innovation Team Pro-gram(No.HITTY-20190013).
文摘1.Introduction During massive data movements in digital computing systems,several issues have emerged such as high latency,energy ineffi-ciency,and low bandwidth due to the physical separation of pro-cessor and memory units(so-called memory wall)[1-3].To miti-gate the data-movement limitations,three-dimensional(3D)chip integration becomes an optimal solution within von Neumann ar-chitecture since the dense vertical interconnections shorten the distance between chips[4,5].However,the extensively used micro solder bumps for 3D chip stacking impede the further improve-ment of interconnection pitch(<10μm).In this scenario,the Cu/SiO_(2) hybrid bonding technology came into being.Owing to the coexistence of planarized Cu connections and SiO_(2) layers,Cu/SiO_(2) hybrid bonding is the desirable enabler of submicron ultra-dense integration(<1μm),which benefits from Cu-Cu and SiO_(2)-SiO_(2) homogeneous direct bonding replacing micro bumps and underfill[6,7].
基金supported by Shanghai Agriculture Applied Technology Development Program of China(2019-02-08-00-08F01124)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(51521004)the National Natural Science Foundation of China(52036002)。