1 In Lichuan,Central China's Hubei Province,a family's dedication to preserving cultural heritage has become a beacon(灯塔)of inspiration.The Sun family,comprised of father Sun Hui and son Sun Ru,has been the ...1 In Lichuan,Central China's Hubei Province,a family's dedication to preserving cultural heritage has become a beacon(灯塔)of inspiration.The Sun family,comprised of father Sun Hui and son Sun Ru,has been the backbone of the national cultural relics census in Lichuan since the 1970s,embodying the nation's spirit of protecting cultural treasures.展开更多
Metal nanoclusters(MNCs)possess distinct chemical properties due to their diverse electronic structures.As a class of promising model catalysts,it is of importance to explore the relationship between their structures ...Metal nanoclusters(MNCs)possess distinct chemical properties due to their diverse electronic structures.As a class of promising model catalysts,it is of importance to explore the relationship between their structures and properties.However,it is still challenging to get highly active and stable MNCs as surface ligands can hinder their activities,while a complete lack of surface ligand protection can lead to instability.To address this concern,here a series of Pd_(6)nanoclusters(NCs)with varying ligand amounts were synthesized by using Pd_(6)(SC_(6)(C_(2))H_(17))_(12)as precursor and single-walled carbon nanotube(s-CNT)as carrier through treating the composite at different temperatures and times.展开更多
Deep learning’s widespread dependence on large datasets raises privacy concerns due to the potential presence of sensitive information.Differential privacy stands out as a crucial method for preserving privacy,garner...Deep learning’s widespread dependence on large datasets raises privacy concerns due to the potential presence of sensitive information.Differential privacy stands out as a crucial method for preserving privacy,garnering significant interest for its ability to offer robust and verifiable privacy safeguards during data training.However,classic differentially private learning introduces the same level of noise into the gradients across training iterations,which affects the trade-off between model utility and privacy guarantees.To address this issue,an adaptive differential privacy mechanism was proposed in this paper,which dynamically adjusts the privacy budget at the layer-level as training progresses to resist member inference attacks.Specifically,an equal privacy budget is initially allocated to each layer.Subsequently,as training advances,the privacy budget for layers closer to the output is reduced(adding more noise),while the budget for layers closer to the input is increased.The adjustment magnitude depends on the training iterations and is automatically determined based on the iteration count.This dynamic allocation provides a simple process for adjusting privacy budgets,alleviating the burden on users to tweak parameters and ensuring that privacy preservation strategies align with training progress.Extensive experiments on five well-known datasets indicate that the proposed method outperforms competing methods in terms of accuracy and resilience against membership inference attacks.展开更多
Along China’s 18,000-kilometer mainland coastline and across its 4.73 million square kilometers of territorial waters,scenes of crystal-clear waves lapping against pristine shores with flocks of seabirds soaring over...Along China’s 18,000-kilometer mainland coastline and across its 4.73 million square kilometers of territorial waters,scenes of crystal-clear waves lapping against pristine shores with flocks of seabirds soaring overhead are becoming increasingly common.The concept of“harmony between humanity and the sea”has been widely embraced by Chinese people,and numerous bays have become showcases for ecological beauty.展开更多
In light of increasingly worsening environmental pollution,this paper,through comparing different attitudes towards the relationship between man and nature in Chinese and the western culture,points out rebuilding a ha...In light of increasingly worsening environmental pollution,this paper,through comparing different attitudes towards the relationship between man and nature in Chinese and the western culture,points out rebuilding a harmonious relationship between man and nature is the common object of human being,and appeals to people to shake off man-centered thinking pattern,and to treat nature as our friend.展开更多
In order to investigate the protective effect of aloe anthraquinones on growth and development of soybean against ultraviolet B radiation stress from the morphological structure and physio-chemical indices. The result...In order to investigate the protective effect of aloe anthraquinones on growth and development of soybean against ultraviolet B radiation stress from the morphological structure and physio-chemical indices. The results showed that, stressed by the enhanced ultraviolet b radiation, the soybean gave a dwarfed plant, shrunken leaf area and decreased photosynthetic pigment, while an ascended MDA content. Spraying aloe anthraquinones effectively relieved the reductions of chloro- phyll content and biomass and decreased the production of MDA under the radia- tion of UV-B. Moreover, under the UV-B radiation, waxy substances on epidermal cells increased remarkably and the stomas showed obvious subsidence, while spraying aloe anthraquinones could maintain the structure and shape of cells similar to that under natural light, and the stomas subsidence as well.展开更多
Focal ischemic stroke（FIS）results from the lack of blood flow in a particular region of the brain and accounts for about 80%of all human strokes.Although tremendous efforts have been made in translational research,t...Focal ischemic stroke（FIS）results from the lack of blood flow in a particular region of the brain and accounts for about 80%of all human strokes.Although tremendous efforts have been made in translational research,the treatment strategies are still limited.Tissue plasminogen activator is the only FDA-approved drug currently available for acute stroke treatment,展开更多
The models of two qubits separately trapped in two independent Markovian or non-Markovian environments have been investigated. The distinction of the two-qubit entanglement dynamics in different environments has also ...The models of two qubits separately trapped in two independent Markovian or non-Markovian environments have been investigated. The distinction of the two-qubit entanglement dynamics in different environments has also been discussed in detail. The results show that, in non-Markovian environments, the possible usage time of entanglement can be extended due to its memory effect. On the other hand, we note that, compared to Markovian environments, the two-qubit entanglement could be protected better in non-Markovian environments by modulating the detuning between qubits and cavities. Finally, an intuitive physicM interpretation for these results is given.展开更多
The intrinsically safe Zn||I_(2) battery,one of the leading candidates aiming to replace traditional Pb-acid batteries,is still seriously suffering from short shelf and cycling lifespan,due to the uncontrolled I_(3)^(...The intrinsically safe Zn||I_(2) battery,one of the leading candidates aiming to replace traditional Pb-acid batteries,is still seriously suffering from short shelf and cycling lifespan,due to the uncontrolled I_(3)^(−)-shuttling and dynamic parasitic reactions on Zn anodes.Considering the fact that almost all these detrimental processes terminate on the surfaces of Zn anodes,modifying Zn anodes’surface with protecting layers should be one of the most straightforward and thorough approaches to restrain these processes.Herein,a facile zeolite-based cation-exchange protecting layer is designed to comprehensively suppress the unfavored parasitic reactions on the Zn anodes.The negatively-charged cavities in the zeolite lattice provide highly accessible migration channels for Zn^(2+),while blocking anions and electrolyte from passing through.This low-cost cation-exchange protecting layer can simultaneously suppress self-discharge,anode corrosion/passivation,and Zn dendrite growth,awarding the Zn||I_(2) batteries with ultra-long cycle life(91.92%capacity retention after 5600 cycles at 2 A g^(−1)),high coulombic efficiencies(99.76%in average)and large capacity(203–196 mAh g^(−1) at 0.2 A g^(−1)).This work provides a highly affordable approach for the construction of high-performance Zn-I_(2) aqueous batteries.展开更多
A new IL-supported diol, 1-（2,3-dihydroxypropyl）-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS （ESI）. Its physical properties such as freezing po...A new IL-supported diol, 1-（2,3-dihydroxypropyl）-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS （ESI）. Its physical properties such as freezing point, solubility and specific gravity and thermal stability were determined. Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated.展开更多
On-surface synthesis of semiconducting graphdiyne nanowires usually suffer severe side reactions owing to the high reactivity of the butadiynylene units at noble metal surfaces,limiting the production of isolated nano...On-surface synthesis of semiconducting graphdiyne nanowires usually suffer severe side reactions owing to the high reactivity of the butadiynylene units at noble metal surfaces,limiting the production of isolated nanowires. In this work, we report the high-yield synthesis of branchless graphdiyne nanowires [-C≡C-Ph2-C≡C-]nvia on-surface Ullmann coupling of 1,4-bis（4-bromophenyl）-1,3-butadiyne molecules with chemical vapor deposition method.Non-contact atomic force microscopy with single-bond resolution reveals that single gold adatoms act as effective protecting groups for butadiynylene units by forming Au-π ligand bonds, preventing unwanted branched coupling reactions and enabling the synthesis of ultralong isolated graphdiyne nanowires. This study will stimulate further investigation on the role of various surface adatoms in protecting on-surface reactions.展开更多
Objective To study the protecting effects and mechanism of betaine hydrochloride on hepatic ischemia-reperfusion injury in rats.Methods Fourty SD rats were randomly divided into 5 groups(8 animals in each group):sham-...Objective To study the protecting effects and mechanism of betaine hydrochloride on hepatic ischemia-reperfusion injury in rats.Methods Fourty SD rats were randomly divided into 5 groups(8 animals in each group):sham-operated control group(A),hepatic ischemia-reperfusion group(B),200 mg·kg-1 400 mg·kg-1 800 mg·kg-1 betaine hydrochloride+hepatic ischemia-reperfusion group(C、D、E).betaine hydrochloride was administered to animals byoral route in group C、D、E for 7 days before ischemia.A、B group was administered with NS.Made the animal model of part hepatic ischemia-reperfusion.Serum alanine aminotransferase(ALT),aspartate aminotransferase(AST)levels in the blood and themalondialdehyde(MDA),superoxide dismutase(SOD),protein content in hepatic tissue were determined after the liver had been reperfused for 24 hours;the hepatic tissue was examined under lightmicroscope and the cell apoptosis was demonstrated with flow cytometry.Results ALT,AST,MDA increased and SOD decreased significantly in B group when compared those in the A group(P<0.05),Hepatic apoptosis was significantly increased;ALT,AST,MDA decreased and SOD increased significantly in betaine hydrochloride 200 mg·kg-1(C)group when compared those in the B group(P<0.05).Hepatic apoptosis was significantly lower,The histologic changes of the liver tissue under lightmicroscope in the C group was more easer than in the I/R group(B).Conclusions Betaine hydrochloride has the ability to scavenge oxygen free radical(OFR),reduce lipid peroxidation and inhibition of apoptosis.So it can protect the rats liver damaged by ischemia-reperfusion.展开更多
Imine bonds are among the most explored building motifs in dynamic chemistry,polymers,and materials,and yet,their acid-resistance remains a longstanding issue.Herein we demonstrate a concept of internal protecting gro...Imine bonds are among the most explored building motifs in dynamic chemistry,polymers,and materials,and yet,their acid-resistance remains a longstanding issue.Herein we demonstrate a concept of internal protecting groups for improving the kinetic stability of dynamic imine bonds and polymers.Systematic examination of structure-reactivity relationship of a series of aldehydes/imines bearing a neighboring carboxyl allowed uncovering of required structural features for dynamically masking imine bonds with cyclic structures.Mechanistic studies indicated that noncovalent interactions along with sterics control the ringchain equilibrium and the stability of imine bonds.The incorporation of internal protecting groups into imine polymers further enabled their controlled stability in acidic media.Moreover,a combination of dynamic covalent network and coordination supramolecular network provided a facile means for the modulation of luminescent and mechanical properties of polymers.The strategies and results reported should be beneficial to molecular assemblies,dynamic polymers,biological delivery,and intelligent materials.展开更多
A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chl...A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites.展开更多
The pharmacodynamic active parts of protecting liver of Peristrope japonica (thunb.)Bremek were identified. Rat acute liver injury model was induced by D-galactosamine (D-GlaN). The active parts were identified on the...The pharmacodynamic active parts of protecting liver of Peristrope japonica (thunb.)Bremek were identified. Rat acute liver injury model was induced by D-galactosamine (D-GlaN). The active parts were identified on the whole extraction and 4 fractions. The results showed that the pharmacodynamic active parts of Peristrope japonica were the n-BuOH fraction.展开更多
With the control mode of value-added network services equipment changing from bypass intervention to serial control, in order to minimize the security problems which are caused by the failure of the network equipment,...With the control mode of value-added network services equipment changing from bypass intervention to serial control, in order to minimize the security problems which are caused by the failure of the network equipment, this paper proposes a stable, fast and intelligent network bypass protection system combined with the ARM embedded system—Linux platform. In practical application, the system can automatically skip the broken-down device node to protect the network to be unobstructed. With the features of fast response, stable operation, low power consumption, and the flexible of combination, the scheme is proved to have large practical value.展开更多
Amino group protective strategy has consequently emerged in multistep organic synthesis.Easy and selective deprotection procedures are crucial to facilitate the chemical transformation.Recently,Zhang’s group from Hen...Amino group protective strategy has consequently emerged in multistep organic synthesis.Easy and selective deprotection procedures are crucial to facilitate the chemical transformation.Recently,Zhang’s group from Henan Normal University collaborating with Chen’s group of Nankai University developed a novel strategy for the regiospecific cleavage of inert aryl C-N bonds in N-aryl amides by hypervalent iodine(V)reagents.These procedures allow removal of sort of aryl groups under mild conditions to give primary amides in high efficiency.It bestows these aryl groups with the characteristics of amino protecting groups that might be the supplement of amino protecting group chemistry.展开更多
Benzyl protecting protocol was first employed in two routes for the concise synthesis of dopexamine dihydrochloride.This protecting group could be cleanly removed under mild condition and no unacceptable ion was broug...Benzyl protecting protocol was first employed in two routes for the concise synthesis of dopexamine dihydrochloride.This protecting group could be cleanly removed under mild condition and no unacceptable ion was brought to the final product.The total yield of route I was 43.8% from phenylacetic acid,while it was 54.1% of route II from 2-（3,4-bis（benzyloxy）phenyl）acetic acid.The titration purity of the final product was more than 99.5%,while any single or total impurities met the known standard of the drug by HPLC analysis.The measured residual palladium met an acceptable limit（〈1 ppm） as an API for injection.展开更多
WHEN Beijing has a day with pristine blue skies,it trends immediately on Wechat(China’s premier social media app).The rare occurrence of“Beijing Blue”and media chatter about such rare weather is indicative of the C...WHEN Beijing has a day with pristine blue skies,it trends immediately on Wechat(China’s premier social media app).The rare occurrence of“Beijing Blue”and media chatter about such rare weather is indicative of the Chinese capital’s ongoing battle with polluted air and is symbolic of the severe pressure the country faces in the feld of environmental protection.展开更多
BACKGROUND ; Phycecyanin can anti-oxidize and clear free radial. Whether its protective effect on brain is related to Caspase-3, the promoter and operator of apoptosis, is highly concerned. OBJECTIVE： To observe phyc...BACKGROUND ; Phycecyanin can anti-oxidize and clear free radial. Whether its protective effect on brain is related to Caspase-3, the promoter and operator of apoptosis, is highly concerned. OBJECTIVE： To observe phycocyanin for protecting nerve function and reducing the size of cerebral infarction of rats with brain ischemia-reperfusion and its effect on the expression of Cespese-3 mRNA. DESIGN ： A randomized controlled experiment. SETTING ： Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University MATERIALS： Totally 84 adult healthy female Wistar rats, weighing 210 to 250 g, of clean grade, were provided by the Animal Experimental Center of Shandong University. Phycocyanin （Institute of Oceanography of Chinese Academy of Sciences） was used. METHODS： This experiment was carried out in the Key Laboratory for Prevention and Treatment of Brain Diseases during May to December 2005. ① The rats were randomized into sham-operation group （n=4）, control group （n=-40） and phycocyanin-treated group （n=-40）. Middle cerebral artery occlusion/reperfusion （MACO/R） models were created on the rats of control and phycocyanin-treated groups with suture-occluded method by inserting a thread into left side extemal-internal carotid artery. In the sham-operatien group, inserting suture was omitted. After ischemia for 1 hour and reperfusion for 2 hours, suspension of phycocyanin was intragastdcaUy administrated into the rats of the phycocyanin-treated group at 100 mg/kg , and the same volume of normal saline was isochrenously administrated into the rats of control group as the same. ② Six rats were chosen respectively from the control group and phycocyanin-treated group, then neurologic impairment degrees of rats were evaluated according to Bederson＇s grading. ③ Six rats were chosen respectively from the control and phycocyanin-treated groups. The isolated brain tissue was stained with tdphenyltetrazolium chloride, and then the size of cerebral infarction was calculated with HPIAS-1000 image analytical system by calculating the ratio of cerebral infarction size at each layer and contralateral hemisphere size of the same layer. ④ Twenty--eight rats were chosen respectively from the control and phycocyanin-treated groups, Brain tissue was harvested at reperfusion for 6,12,24 hours and for 2,3,7 and 14 days after ischemia for 1 hour, respectively, 4 rats at each time point. Brain tissue of 4 rats of sham-opera- tion group was harvested at the 24^th hour after operation. Brain tissue sections were performed in situ hybridization detection of Cespase-3 mRNA. MAIN OUTCOME MEASURES： Comparison of neurologic impairment degree, cerebral infarction size and the expression of brain tissue Caspase-3 mRNA of rats between two groups RESULTS： Totally 84 rats entered the stage of result analysis. ① Bederson＇s scores at ischemia and reperfusion for 24 and 48 hours were significantly lower in the phycocyanin-treated group than in the control group（P 〈 0.05）. ② After brain ischemia and reperfusion, the infarction area was the largest in the 3^rc layer in both control and phycocyanin-treated group, which was（25.23±0,47）% and（23.09±120） %, respectively, and the size of infarction area in the 2^nd layer to the 5^th layer was significantly smaller in the phycocyanin-treated group than in the control group （P 〈 0.05）. ③Positive cell counts of brain tissue Caspase-3 mRNA： The number of positive cells of Caspase-3 mRNA of control group was increased from cerebral ischemia and reperfusion 6 hours, reached the peak at ischemia and reperfusion 24 hours, began to decrease 2 days later and positive cells of Caspese-3 mRNA were still expressed on the 14^th day after reperfusion. At ischemia and reperfusion 6,12 and 24 hours as well as 2,3,7 and 14 days, positive cell counts of Caspase-3 at peripheral ischemic area were significantly lower in the phycocyanin-treated greup[（70.67 ±3.65）, （85.06±4.79）, （119.54±5.37）,（74.26±2.19）, （62.06±3.34）, （23.11±1.89）, （10.75±2.63）/visual field] than in the control group [（94.38±8 28）, （108.81 ±16.11）, （140.88±14.47）, （98.13±11.31）, （81.03±9.31）, （31.22±8.86）, （16.06±5.96）Nisual field] （ P 〈 0.05）; and those at central ischemic area were also significantly lower in the phycocyanin-treated group [（33.86±4.01）, （39.51±3.46）, （50.96 ±2.53）, （43.07±4.09）, （36.25 ±3.72）, （9.03±3.87）, （4.91±5.59）/visual field ]than in the control group [（51.35±2.13）, （54.87±3.42）, （61.77±4.94）, （55.69±6.06）, （49.01 ±5.73） ,（12.84±3.37）, （7.32±2.39）/visual field]（P 〈 0.05）. CONCLUSION ： Phycocyanin can obviously improve the neurologic function, reduce the size of brain infarction and down-regulate the expression of Caspase-3 mRNA of rats with ischemia and reperfusion injury, thus protect brain.展开更多
文摘1 In Lichuan,Central China's Hubei Province,a family's dedication to preserving cultural heritage has become a beacon(灯塔)of inspiration.The Sun family,comprised of father Sun Hui and son Sun Ru,has been the backbone of the national cultural relics census in Lichuan since the 1970s,embodying the nation's spirit of protecting cultural treasures.
基金financially supported by the Natural Science Foundation of Guangxi,China(Nos.2019GXNSFGA245003 and 2021GXNSFBA220058)the National Natural Science Foundation of China(Nos.22272036 and 22362008)+2 种基金Guangxi Technology Base and Talent Subject,China(GUIKE AD23026272)Guangxi Normal University Research Grant,China(No.2022TD)Innovation Project of Guangxi Graduate Education(No.XYCSR2023018)。
文摘Metal nanoclusters(MNCs)possess distinct chemical properties due to their diverse electronic structures.As a class of promising model catalysts,it is of importance to explore the relationship between their structures and properties.However,it is still challenging to get highly active and stable MNCs as surface ligands can hinder their activities,while a complete lack of surface ligand protection can lead to instability.To address this concern,here a series of Pd_(6)nanoclusters(NCs)with varying ligand amounts were synthesized by using Pd_(6)(SC_(6)(C_(2))H_(17))_(12)as precursor and single-walled carbon nanotube(s-CNT)as carrier through treating the composite at different temperatures and times.
基金supported by the National Natural Science Foundation of China(Grant No.62462022)the Hainan Province Science and Technology Special Fund(Grants No.ZDYF2022GXJS229).
文摘Deep learning’s widespread dependence on large datasets raises privacy concerns due to the potential presence of sensitive information.Differential privacy stands out as a crucial method for preserving privacy,garnering significant interest for its ability to offer robust and verifiable privacy safeguards during data training.However,classic differentially private learning introduces the same level of noise into the gradients across training iterations,which affects the trade-off between model utility and privacy guarantees.To address this issue,an adaptive differential privacy mechanism was proposed in this paper,which dynamically adjusts the privacy budget at the layer-level as training progresses to resist member inference attacks.Specifically,an equal privacy budget is initially allocated to each layer.Subsequently,as training advances,the privacy budget for layers closer to the output is reduced(adding more noise),while the budget for layers closer to the input is increased.The adjustment magnitude depends on the training iterations and is automatically determined based on the iteration count.This dynamic allocation provides a simple process for adjusting privacy budgets,alleviating the burden on users to tweak parameters and ensuring that privacy preservation strategies align with training progress.Extensive experiments on five well-known datasets indicate that the proposed method outperforms competing methods in terms of accuracy and resilience against membership inference attacks.
文摘Along China’s 18,000-kilometer mainland coastline and across its 4.73 million square kilometers of territorial waters,scenes of crystal-clear waves lapping against pristine shores with flocks of seabirds soaring overhead are becoming increasingly common.The concept of“harmony between humanity and the sea”has been widely embraced by Chinese people,and numerous bays have become showcases for ecological beauty.
文摘In light of increasingly worsening environmental pollution,this paper,through comparing different attitudes towards the relationship between man and nature in Chinese and the western culture,points out rebuilding a harmonious relationship between man and nature is the common object of human being,and appeals to people to shake off man-centered thinking pattern,and to treat nature as our friend.
基金Supported by National Natural Science Foundation of China(31270225)~~
文摘In order to investigate the protective effect of aloe anthraquinones on growth and development of soybean against ultraviolet B radiation stress from the morphological structure and physio-chemical indices. The results showed that, stressed by the enhanced ultraviolet b radiation, the soybean gave a dwarfed plant, shrunken leaf area and decreased photosynthetic pigment, while an ascended MDA content. Spraying aloe anthraquinones effectively relieved the reductions of chloro- phyll content and biomass and decreased the production of MDA under the radia- tion of UV-B. Moreover, under the UV-B radiation, waxy substances on epidermal cells increased remarkably and the stomas showed obvious subsidence, while spraying aloe anthraquinones could maintain the structure and shape of cells similar to that under natural light, and the stomas subsidence as well.
基金supported by NIH NS069726 and NS094539America Heart Association 13GRANT17020004(to SD)
文摘Focal ischemic stroke（FIS）results from the lack of blood flow in a particular region of the brain and accounts for about 80%of all human strokes.Although tremendous efforts have been made in translational research,the treatment strategies are still limited.Tissue plasminogen activator is the only FDA-approved drug currently available for acute stroke treatment,
文摘The models of two qubits separately trapped in two independent Markovian or non-Markovian environments have been investigated. The distinction of the two-qubit entanglement dynamics in different environments has also been discussed in detail. The results show that, in non-Markovian environments, the possible usage time of entanglement can be extended due to its memory effect. On the other hand, we note that, compared to Markovian environments, the two-qubit entanglement could be protected better in non-Markovian environments by modulating the detuning between qubits and cavities. Finally, an intuitive physicM interpretation for these results is given.
基金The authors thank the National Natural Science Foundation of China(51502194,22133005,21973107,and 22103093)the Natural Science Foundation of Shandong(ZR2020ME024)+2 种基金the Science and Technology Commission of Shanghai Municipality(21ZR1472900)the Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province(HPK202103)for financial supportOpen access funding provided by Shanghai Jiao Tong University
文摘The intrinsically safe Zn||I_(2) battery,one of the leading candidates aiming to replace traditional Pb-acid batteries,is still seriously suffering from short shelf and cycling lifespan,due to the uncontrolled I_(3)^(−)-shuttling and dynamic parasitic reactions on Zn anodes.Considering the fact that almost all these detrimental processes terminate on the surfaces of Zn anodes,modifying Zn anodes’surface with protecting layers should be one of the most straightforward and thorough approaches to restrain these processes.Herein,a facile zeolite-based cation-exchange protecting layer is designed to comprehensively suppress the unfavored parasitic reactions on the Zn anodes.The negatively-charged cavities in the zeolite lattice provide highly accessible migration channels for Zn^(2+),while blocking anions and electrolyte from passing through.This low-cost cation-exchange protecting layer can simultaneously suppress self-discharge,anode corrosion/passivation,and Zn dendrite growth,awarding the Zn||I_(2) batteries with ultra-long cycle life(91.92%capacity retention after 5600 cycles at 2 A g^(−1)),high coulombic efficiencies(99.76%in average)and large capacity(203–196 mAh g^(−1) at 0.2 A g^(−1)).This work provides a highly affordable approach for the construction of high-performance Zn-I_(2) aqueous batteries.
基金the National Natural Science Foundation of China(No.20533010,20673039)the Science&Technology Commission of Shanghai Municipality(No.06JC14023)for financial support.
文摘A new IL-supported diol, 1-（2,3-dihydroxypropyl）-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS （ESI）. Its physical properties such as freezing point, solubility and specific gravity and thermal stability were determined. Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated.
基金the National Key R&D Program of China(No.2016YFA0200603 No.2017YFA0205004)the Anhui Initiative in Quantum Information Technologies(AHY090300)+2 种基金the National Natural Science Foundation of China(No.21473174)the Fundamental Research Funds for the Central Universities(No.WK2060190084 and No.WK2340000082)Ai-di Zhao acknowledges a fellow-ship from the Youth Innovation Promotion Association of Chinese Academy of Science(2011322).
文摘On-surface synthesis of semiconducting graphdiyne nanowires usually suffer severe side reactions owing to the high reactivity of the butadiynylene units at noble metal surfaces,limiting the production of isolated nanowires. In this work, we report the high-yield synthesis of branchless graphdiyne nanowires [-C≡C-Ph2-C≡C-]nvia on-surface Ullmann coupling of 1,4-bis（4-bromophenyl）-1,3-butadiyne molecules with chemical vapor deposition method.Non-contact atomic force microscopy with single-bond resolution reveals that single gold adatoms act as effective protecting groups for butadiynylene units by forming Au-π ligand bonds, preventing unwanted branched coupling reactions and enabling the synthesis of ultralong isolated graphdiyne nanowires. This study will stimulate further investigation on the role of various surface adatoms in protecting on-surface reactions.
文摘Objective To study the protecting effects and mechanism of betaine hydrochloride on hepatic ischemia-reperfusion injury in rats.Methods Fourty SD rats were randomly divided into 5 groups(8 animals in each group):sham-operated control group(A),hepatic ischemia-reperfusion group(B),200 mg·kg-1 400 mg·kg-1 800 mg·kg-1 betaine hydrochloride+hepatic ischemia-reperfusion group(C、D、E).betaine hydrochloride was administered to animals byoral route in group C、D、E for 7 days before ischemia.A、B group was administered with NS.Made the animal model of part hepatic ischemia-reperfusion.Serum alanine aminotransferase(ALT),aspartate aminotransferase(AST)levels in the blood and themalondialdehyde(MDA),superoxide dismutase(SOD),protein content in hepatic tissue were determined after the liver had been reperfused for 24 hours;the hepatic tissue was examined under lightmicroscope and the cell apoptosis was demonstrated with flow cytometry.Results ALT,AST,MDA increased and SOD decreased significantly in B group when compared those in the A group(P<0.05),Hepatic apoptosis was significantly increased;ALT,AST,MDA decreased and SOD increased significantly in betaine hydrochloride 200 mg·kg-1(C)group when compared those in the B group(P<0.05).Hepatic apoptosis was significantly lower,The histologic changes of the liver tissue under lightmicroscope in the C group was more easer than in the I/R group(B).Conclusions Betaine hydrochloride has the ability to scavenge oxygen free radical(OFR),reduce lipid peroxidation and inhibition of apoptosis.So it can protect the rats liver damaged by ischemia-reperfusion.
基金the National Natural Science Foundation of China(NSFC,Nos.22071247,92156010,22101283,and 22101284)the Key Research Program of Frontier Sciences(No.QYZDBSSW-SLH030)of the CAS+1 种基金Natural Science Foundation of Fujian Province(Nos.2020J06035 and 2022J05085)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZR112)for support.
文摘Imine bonds are among the most explored building motifs in dynamic chemistry,polymers,and materials,and yet,their acid-resistance remains a longstanding issue.Herein we demonstrate a concept of internal protecting groups for improving the kinetic stability of dynamic imine bonds and polymers.Systematic examination of structure-reactivity relationship of a series of aldehydes/imines bearing a neighboring carboxyl allowed uncovering of required structural features for dynamically masking imine bonds with cyclic structures.Mechanistic studies indicated that noncovalent interactions along with sterics control the ringchain equilibrium and the stability of imine bonds.The incorporation of internal protecting groups into imine polymers further enabled their controlled stability in acidic media.Moreover,a combination of dynamic covalent network and coordination supramolecular network provided a facile means for the modulation of luminescent and mechanical properties of polymers.The strategies and results reported should be beneficial to molecular assemblies,dynamic polymers,biological delivery,and intelligent materials.
基金The project is supported by the National Natural Science Foundation of China.
文摘A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites.
文摘The pharmacodynamic active parts of protecting liver of Peristrope japonica (thunb.)Bremek were identified. Rat acute liver injury model was induced by D-galactosamine (D-GlaN). The active parts were identified on the whole extraction and 4 fractions. The results showed that the pharmacodynamic active parts of Peristrope japonica were the n-BuOH fraction.
文摘With the control mode of value-added network services equipment changing from bypass intervention to serial control, in order to minimize the security problems which are caused by the failure of the network equipment, this paper proposes a stable, fast and intelligent network bypass protection system combined with the ARM embedded system—Linux platform. In practical application, the system can automatically skip the broken-down device node to protect the network to be unobstructed. With the features of fast response, stable operation, low power consumption, and the flexible of combination, the scheme is proved to have large practical value.
文摘Amino group protective strategy has consequently emerged in multistep organic synthesis.Easy and selective deprotection procedures are crucial to facilitate the chemical transformation.Recently,Zhang’s group from Henan Normal University collaborating with Chen’s group of Nankai University developed a novel strategy for the regiospecific cleavage of inert aryl C-N bonds in N-aryl amides by hypervalent iodine(V)reagents.These procedures allow removal of sort of aryl groups under mild conditions to give primary amides in high efficiency.It bestows these aryl groups with the characteristics of amino protecting groups that might be the supplement of amino protecting group chemistry.
基金supported by Program for Innovative Research Team of the Ministry of Education and Program for Liaoning Innovative Research Team in UniversityShenyang Shuangding Pharmaceutical Co.,LTD.,Shenyang,China
文摘Benzyl protecting protocol was first employed in two routes for the concise synthesis of dopexamine dihydrochloride.This protecting group could be cleanly removed under mild condition and no unacceptable ion was brought to the final product.The total yield of route I was 43.8% from phenylacetic acid,while it was 54.1% of route II from 2-（3,4-bis（benzyloxy）phenyl）acetic acid.The titration purity of the final product was more than 99.5%,while any single or total impurities met the known standard of the drug by HPLC analysis.The measured residual palladium met an acceptable limit（〈1 ppm） as an API for injection.
文摘WHEN Beijing has a day with pristine blue skies,it trends immediately on Wechat(China’s premier social media app).The rare occurrence of“Beijing Blue”and media chatter about such rare weather is indicative of the Chinese capital’s ongoing battle with polluted air and is symbolic of the severe pressure the country faces in the feld of environmental protection.
文摘BACKGROUND ; Phycecyanin can anti-oxidize and clear free radial. Whether its protective effect on brain is related to Caspase-3, the promoter and operator of apoptosis, is highly concerned. OBJECTIVE： To observe phycocyanin for protecting nerve function and reducing the size of cerebral infarction of rats with brain ischemia-reperfusion and its effect on the expression of Cespese-3 mRNA. DESIGN ： A randomized controlled experiment. SETTING ： Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University MATERIALS： Totally 84 adult healthy female Wistar rats, weighing 210 to 250 g, of clean grade, were provided by the Animal Experimental Center of Shandong University. Phycocyanin （Institute of Oceanography of Chinese Academy of Sciences） was used. METHODS： This experiment was carried out in the Key Laboratory for Prevention and Treatment of Brain Diseases during May to December 2005. ① The rats were randomized into sham-operation group （n=4）, control group （n=-40） and phycocyanin-treated group （n=-40）. Middle cerebral artery occlusion/reperfusion （MACO/R） models were created on the rats of control and phycocyanin-treated groups with suture-occluded method by inserting a thread into left side extemal-internal carotid artery. In the sham-operatien group, inserting suture was omitted. After ischemia for 1 hour and reperfusion for 2 hours, suspension of phycocyanin was intragastdcaUy administrated into the rats of the phycocyanin-treated group at 100 mg/kg , and the same volume of normal saline was isochrenously administrated into the rats of control group as the same. ② Six rats were chosen respectively from the control group and phycocyanin-treated group, then neurologic impairment degrees of rats were evaluated according to Bederson＇s grading. ③ Six rats were chosen respectively from the control and phycocyanin-treated groups. The isolated brain tissue was stained with tdphenyltetrazolium chloride, and then the size of cerebral infarction was calculated with HPIAS-1000 image analytical system by calculating the ratio of cerebral infarction size at each layer and contralateral hemisphere size of the same layer. ④ Twenty--eight rats were chosen respectively from the control and phycocyanin-treated groups, Brain tissue was harvested at reperfusion for 6,12,24 hours and for 2,3,7 and 14 days after ischemia for 1 hour, respectively, 4 rats at each time point. Brain tissue of 4 rats of sham-opera- tion group was harvested at the 24^th hour after operation. Brain tissue sections were performed in situ hybridization detection of Cespase-3 mRNA. MAIN OUTCOME MEASURES： Comparison of neurologic impairment degree, cerebral infarction size and the expression of brain tissue Caspase-3 mRNA of rats between two groups RESULTS： Totally 84 rats entered the stage of result analysis. ① Bederson＇s scores at ischemia and reperfusion for 24 and 48 hours were significantly lower in the phycocyanin-treated group than in the control group（P 〈 0.05）. ② After brain ischemia and reperfusion, the infarction area was the largest in the 3^rc layer in both control and phycocyanin-treated group, which was（25.23±0,47）% and（23.09±120） %, respectively, and the size of infarction area in the 2^nd layer to the 5^th layer was significantly smaller in the phycocyanin-treated group than in the control group （P 〈 0.05）. ③Positive cell counts of brain tissue Caspase-3 mRNA： The number of positive cells of Caspase-3 mRNA of control group was increased from cerebral ischemia and reperfusion 6 hours, reached the peak at ischemia and reperfusion 24 hours, began to decrease 2 days later and positive cells of Caspese-3 mRNA were still expressed on the 14^th day after reperfusion. At ischemia and reperfusion 6,12 and 24 hours as well as 2,3,7 and 14 days, positive cell counts of Caspase-3 at peripheral ischemic area were significantly lower in the phycocyanin-treated greup[（70.67 ±3.65）, （85.06±4.79）, （119.54±5.37）,（74.26±2.19）, （62.06±3.34）, （23.11±1.89）, （10.75±2.63）/visual field] than in the control group [（94.38±8 28）, （108.81 ±16.11）, （140.88±14.47）, （98.13±11.31）, （81.03±9.31）, （31.22±8.86）, （16.06±5.96）Nisual field] （ P 〈 0.05）; and those at central ischemic area were also significantly lower in the phycocyanin-treated group [（33.86±4.01）, （39.51±3.46）, （50.96 ±2.53）, （43.07±4.09）, （36.25 ±3.72）, （9.03±3.87）, （4.91±5.59）/visual field ]than in the control group [（51.35±2.13）, （54.87±3.42）, （61.77±4.94）, （55.69±6.06）, （49.01 ±5.73） ,（12.84±3.37）, （7.32±2.39）/visual field]（P 〈 0.05）. CONCLUSION ： Phycocyanin can obviously improve the neurologic function, reduce the size of brain infarction and down-regulate the expression of Caspase-3 mRNA of rats with ischemia and reperfusion injury, thus protect brain.
