Liquid-phase exfoliation was employed to synthesize Sr_(2)Nb_(3)O_(10) perovskite nanosheets with thicknesses down to 1.76 nm.Transmission electron microscopy(TEM),atomic force microscope(AFM),X-ray photoelectron spec...Liquid-phase exfoliation was employed to synthesize Sr_(2)Nb_(3)O_(10) perovskite nanosheets with thicknesses down to 1.76 nm.Transmission electron microscopy(TEM),atomic force microscope(AFM),X-ray photoelectron spectrometer(XPS),and other characterization techniques were used to evaluate the atomic structure and chemical composition of the exfoliated nanosheets.A UV photodetector based on individual Sr_(2)Nb_(3)O_(10) nanosheets was prepared to demonstrate the application of an ultraviolet(UV) photodetector.The UV photodetector exhibited outstanding photocurrent and responsivity with a responsivity of 3×10^(5) A·W^(-1) at 5 V bias under 280 nm illumination,a photocurrent of 60 nA,and an on/off ratio of 3×10^(2).展开更多
To screen patients with early cervical lesions by analyzing the infection of high-risk Human papillomavirus (HR-HPV). Research Methods: The cervical exfoliated cell specimens and their clinical data were collected. Th...To screen patients with early cervical lesions by analyzing the infection of high-risk Human papillomavirus (HR-HPV). Research Methods: The cervical exfoliated cell specimens and their clinical data were collected. The HPV infection types of the collected specimens were detected by fluorescence quantitative PCR, and the correlation between HPV infection and clinicopathological features was analyzed statistically. Results: 725 cases were HR-HPV positive from 2605 cases, including 15 high-risk types of HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68. Different histological types ranged from NILM to HSIL, and the positive rate of HPV showed an increasing trend with the aggravation of cervical lesions. Conclusion: The positive rate of 15 high-risk HPV types in the collected specimens was 27.8%. Patients with early cervical lesions could be screened for 15 high-risk HPV infection types.展开更多
Spent cathode carbon(SCC)from aluminum electrolysis is a potential graphite resource.However,full use of the SCC remains a challenge,since it contains many hazardous substances(e.g.,fluoride salts,cyanides),encapsulat...Spent cathode carbon(SCC)from aluminum electrolysis is a potential graphite resource.However,full use of the SCC remains a challenge,since it contains many hazardous substances(e.g.,fluoride salts,cyanides),encapsulated within the thick carbon layers and thus posing serious environmental concerns.This work presents a chemical oxidative exfoliation route to achieve the recycling of SCC and the decontaminated SCC with high-valued graphene oxide(GO)-like carbon structures(SCC-GO)is applied as an excellent adsorbent for organic pollutants.Specifically,after the oxidative exfoliation,the embedded hazardous constituents are fully exposed,facilitating their subsequent removal by aqueous leaching.Moreover,benefiting from the enhanced specific surface areas along with abundant O-containing functional groups,the as-produced SCC-GO,shows an adsorption capacity as high as 347 mg·g^(-1)when considering methylene blue as a pollutant model,which exceeds most of the recently reported carbon-based adsorbents.Our study provides a feasible solution for the efficient recycling of hazardous carbonaceous wastes.展开更多
MoS_(2) is a highly promising material for application in lithium-ion battery anodes due to its high theoretical capacity and low cost.However,problems with a fast capacity decay over cycling,especially at the first c...MoS_(2) is a highly promising material for application in lithium-ion battery anodes due to its high theoretical capacity and low cost.However,problems with a fast capacity decay over cycling,especially at the first cycles,and poor rate performance have deterred its practical implementation.Herein,electrodes comprised solely of few-layers 2D MoS_(2) nanosheets have been manufactured by scalable liquid-phase exfoliation and spray deposition methods.The long-standing controversy questioning the reversibility of conversion processes of MoS_(2)-based electrodes was addressed.Raman studies revealed that,in 2D MoS_(2) electrodes,conversion processes are indeed reversible,where nanostructure played a key role.Cycling of the electrodes at high current rates revealed an intriguing phenomenon consisting of a continuously increasing capacity after ca.100-200 cycles.This phenomenon was comprehensively addressed by a variety of electrochemical and microscopy methods that revealed underlying physical activation mechanisms that involved a range of profound electrode structural changes.Activation mechanisms delivered a capacitive electrode of a superior rate performance and cycling stability,as compared to the corresponding pristine electrodes,and to MoS_(2) electrodes previously reported.Herein,we have devised a methodology to overcome the problem of cycling stability of 2D MoS_(2) electrodes.Moreover,activation of electrodes constitutes a methodology that could be applied to enhance the energy storage performance of electrodes based on other 2D nanomaterials,or combinations thereof,strategically combining chemistries to engineer electrodes of superior energy storage properties.展开更多
We report a new facile light-induced strategy to disperse micron-sized aggregated bulk covalent organic frameworks(COFs)into isolated COFs nanoparticles.This was achieved by a series of metal-coordinated COFs,namely C...We report a new facile light-induced strategy to disperse micron-sized aggregated bulk covalent organic frameworks(COFs)into isolated COFs nanoparticles.This was achieved by a series of metal-coordinated COFs,namely COF-909-Cu,-Co or-Fe,where for the first time the diffusio-phoretic propulsion was utilized to design COF-based micro/nanomotors.The mechanism studies revealed that the metal ions decorated in the COF-909 backbone could promote the separation of electron and holes and trigger the production of sufficient ionic and reactive oxygen species under visible light irradiation.In this way,strong light-induced self-diffusiophoretic effect is achieved,resulting in good dispersion of COFs.Among them,COF-909-Fe showed the highest dispersion performance,along with a drastic decrease in particle size from 5μm to500 nm,within only 30 min light irradiation,which is inaccessible by using traditional magnetic stirring or ultrasonication methods.More importantly,benefiting from the outstanding dispersion efficiency,COF-909-Fe micro/nanomotors were demonstrated to be efficient in photocatalytic degradation of tetracycline,about 8 times faster than using traditional magnetic stirring method.This work opens up a new avenue to prepare isolated nanosized COFs in a high-fast,simple,and green manner.展开更多
Disulfide zirconium(ZrS_(2)) is a two-dimensional(2D) transition metal disulfide and has given rise to extensive attention because of its distinctive electronic structure and properties.However,mass production of high...Disulfide zirconium(ZrS_(2)) is a two-dimensional(2D) transition metal disulfide and has given rise to extensive attention because of its distinctive electronic structure and properties.However,mass production of high quality of ZrS_(2)nanosheets to realize their practical application remains a challenge.Here,we have successfully exfoliated the bulk ZrS_(2)powder with the thickness of micron into single and few-layer nanosheets through liquid-phase exfoliation in N-methylpyrrolidone(NMP) assisted via aliphatic amines as intercalators.It is found that the exfoliation yield is as high as 27.3%,which is the record value for the exfoliation of ZrS_(2)nanosheets from bulk ZrS_(2)powder,and 77.1% of ZrS_(2)nanosheets are 2-3 layers.The molecular geometric size and aliphatic amine basicity have important impact on the exfoliation.Furthermore,the ZrS_(2)nanosheets have been used as catalyst in the electrocatalytic dinitrogen reduction with the NH3yield of 57.75 μg h^(-1)mg_(cat.)^(-1),which is twice that by ZrS_(2)nanofibers reported in literature and three times that by the bulk ZrS_(2)powder.Therefore,the liquid phase exfoliation strategy reported here has great potential in mass production of ZrS_(2)nanosheets for high activity electrocatalysis.展开更多
Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and ...Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and corrosion resistance of U-shaped cooling channels made of Al-12Si alloy was examined in depth.The experimental results suggest that as the preheating temperature increased from 273 K to 573 K,the roughness of the inner wall of the cooling channel reduced from 96.6μm to 77.0μm.When the preheating temperature continued to increase to 723 K,the roughness increased to 85.3μm.The wetting between the Al melt and the carbon fiber will reduce micro bubbles and waves on the channel wall as the preheating temperature rises,thereby reducing the roughness.However,with the further increase of preheating temperature,it will increase the solidification time of the Al melt.At this time,the carbon fiber and Al melt will take more time to react,which increases the roughness of the channel wall to a certain extent.The results of exfoliation corrosion show that the larger roughness will aggravate exfoliation corrosion.The prolongation of high temperature reaction time between the carbon fiber and the Al melt will lead to the segregation of Si,which is easy to cause intergranular corrosion.Therefore,reasonable preheating temperature has an important impact on the roughness and corrosion resistance of U-shaped cooling channels.展开更多
The doping of functionalized graphene oxide(GO)in the membranes becomes a promising method for improving the performance of high-temperature proton exchange membrane fuel cells(HT-PEMFC).Phosphonated graphene oxide(PG...The doping of functionalized graphene oxide(GO)in the membranes becomes a promising method for improving the performance of high-temperature proton exchange membrane fuel cells(HT-PEMFC).Phosphonated graphene oxide(PGO)with a P/O ratio of 8.5%was quickly synthesised by one-step electrochemical exfoliation based on a three-dimensiaonal(3D)printed reactor and natural graphite flakes.Compared with the GO prepared by the two-step electrochemical exfoliation method,the PGO synthesized by the one-step electrochemical exfoliation can better improve the performance of the membrane-electrode-assembly(MEA)based on the polybenzimidazole(PBI)membrane in the HTPEMFC.The doping of 1.5 wt%GO synthesised by electrochemical exfoliation with the 2-step method or reactor method in PBI increased the peak power density by 17.4%or 35.4%compared to MEA based on pure PBI membrane at 150℃,respectively.In addition,the doping of PGO in PBI improves its durability under accelerated stress test(AST).展开更多
Background: A subset of cancer is particularly vulnerable to hydration prior to chemotherapy protocols;however, real-world outcomes-based data on pre-hydration elements of patients with tumor is sparse. Case Presentat...Background: A subset of cancer is particularly vulnerable to hydration prior to chemotherapy protocols;however, real-world outcomes-based data on pre-hydration elements of patients with tumor is sparse. Case Presentations: This retrospective case series describes a cohort of adult patients with terminal stage cancer who were seen between July 1, 2023, and September 25, 2023 and underwent various chemotherapy protocols, which, to our knowledge, represents comprehensive analysis of this patient population. We performed a retrospective search of patients identifying 50 cases of the chemotherapies of patients with cancer and extracted the clinical data via individual chart reviews. At the time of diagnosis, 24 patients were prehydrated with NaCl with KCl prior to the chemotherapy against the tumor, and 26 patients were taking normal saline only before undergoing cancer-specific treatment. Hydration and, prior chemotherapeutic agents use were the most common predepositse. Carcinomatosis peritoneii were the most common signs of the terminal stage of cancer within patients. Twenty-four patients were admitted to the hospital and two received NaCl with KCl hydaration prior to the platinum based chemotherapeutic agent treatment. Twenty-six patients received only normal saline hydration. Conclusion: Our data suggest that NaCl with KCl prehydaration results in better prognosis, including reduced tumor burden or decreased lymph node invasion, when compared to other vulnerable patients populations that receive only normal saline hydration. The graphene exfoliation effect of NaCl with KCl may have contributed to these results.展开更多
Guillain-Barré syndrome is a rare but fatal autoimmune disease of unknown origin. Infectious disease is the most common etiology of Guillain-Barré syndrome. We had a 75-year-old female patient with Guillain-...Guillain-Barré syndrome is a rare but fatal autoimmune disease of unknown origin. Infectious disease is the most common etiology of Guillain-Barré syndrome. We had a 75-year-old female patient with Guillain-Barré syndrome and a 90-year-old male patient with facial nerve palsy admitted to our hospital. Both patients experienced recovery from early Guillain-Barré syndrome and peripheral facial nerve palsy after receiving intravenous infusion of NaCl with KCl solution and taking vitamin C.展开更多
Mesenchymal stem cells(MSCs) as a source for regenerative medicine are now the subject of much clinical attention. There are high expectations due to their safety, low tumorigenic risk, and low ethical concerns. MSC t...Mesenchymal stem cells(MSCs) as a source for regenerative medicine are now the subject of much clinical attention. There are high expectations due to their safety, low tumorigenic risk, and low ethical concerns. MSC therapy has been approved for acute graft-versus host diseases since 2015. Tooth-derived MSCs are known to have a great potential in their proliferation and differentiation capacities, even when compared with bone-marrow-derived MSCs. In particular, stem cells from human exfoliated deciduous teeth(SHEDs) are the best candidates for personal cell banking(dental pulp cell bank), because they can be obtained less invasively in the natural process of individual growth. SHEDs are known to differentiate into hepatocytes. There have been several studies showing the effectiveness of SHEDs on the treatment of liver failure in animal models. They may exert their effects either by repopulation of cells in injured liver or by paracrine mechanisms due to their immuneregulatory functions. Moreover, it may be possible to use each individuals' dental pulp cells as a future source of tailor-made differentiated hepatocytes in the context of a bioartificial liver or liver-on-a-chip to screen for drug toxicity.展开更多
AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been i...AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been isolated 5 years ago from human exfoliated deciduous teeth. The undifferentiated stem cells were seeded into mandibular bone through-andthrough defects of 4 dogs. Similar defects in control group were filled with cell-free collagen scaffold. After 12 wk, biopsies were taken and morphometric analysis was performed. The percentage of new bone formation and foreign body reaction were measured in each case. The data were subject to statistical analysis using the Mann-Whitney U and Kruskalwalis statistical tests. Differences at P < 0.05 was considered as significant level.RESULTS: There were no significant differences between control and SHED-seeded groups in connective tissue(P = 0.248), woven bone(P = 0.248) and compact bone(P = 0.082). There were not any side effects in transplanted SHED group such as teratoma or malignancy and abnormalities in this period.CONCLUSION: SHEDs which had been isolated and characterized 5 years ago and stored with cryopreservation banking were capable of proliferation and osteogenesis after 5 years, and no immune response was observed after three months of seeded SHEDs.展开更多
The corrosion behavior of an Al-6Mg-Sc-Zr alloy was studied and compared with that of an Al-6Mg-Zr alloy. The addition of scandium into the Al-6Mg-Zr alloy reduced the susceptibility to exfoliation corrosion. By using...The corrosion behavior of an Al-6Mg-Sc-Zr alloy was studied and compared with that of an Al-6Mg-Zr alloy. The addition of scandium into the Al-6Mg-Zr alloy reduced the susceptibility to exfoliation corrosion. By using the constant load tensile method in a 3.5 wt.% NaCl solution, the resistance to SCC of the Al-6Mg-Sc-Zr alloy was higher than that of the Al-6Mg-Zr alloy. When the specimens were not applied with an anodic current, the Al-6Mg-Sc-Zr alloy was resistance to SCC and no brittle cracking was found on the fracture surface. When an anodic current was applied, the Al-6Mg-Sc-Zr alloy specimens failed as a result of accelerated corrosion rather than SCC. It was believed that the addition of scandium re- sulted in (Al3Sc, Zr) particles that greatly refined grains and promoted the formation of homogeneous discontinuous distribution of β-phase in the alloy base, which much contributed to good corrosion resistance of the Al-6Mg-Sc-Zr alloy.展开更多
The direct coating of graphene sheets obtained by electrochemical exfoliation on commercial paper renders the preparation of highly conductive flexible paper substrate for subsequent deposition of polyaniline (PANi) n...The direct coating of graphene sheets obtained by electrochemical exfoliation on commercial paper renders the preparation of highly conductive flexible paper substrate for subsequent deposition of polyaniline (PANi) nanorods via electrochemical polymerization. The deposit ion of PANi can be well-controlled by adjusting the electrochemical polymerization time, leading to the formation of PANi coated graphene paper (PANi-GP). The as-prepared electrode exhibited high areal capacitance of 176 mF cm^-2 in three-electrode system at a current density of 0.2 mA cm^-2 which is around 10 times larger than that of pris-tine graphene paper due to the pseudocapacitive behavior of PANi. In-situ Raman test was used to determine the molecular changes during redox process of PANi. More importantly, all-solid-state symmetric capacitor assembled with two PANi-GP electrodes in a polymer electrolyte delivered an areal capacitanee of 123 mF cm^-2, corresponding to an areal energy density of 17.1 μWh cm^-2 and an areal power density of 0.25 mW cm^-2. The symmetric capacitor held a capacitive retention of 74.8% after 500 bending tests from 0 to 120°, suggesting the good flexibility and mechanical stability. These results showed the great promising application in flexible energy-storage devices.展开更多
Intensive research effort is currently focused on the development of efficient, reliable, and environmentally safe electrochemical energy storage systems due to the ever-increasing global energy storage demand. Li ion...Intensive research effort is currently focused on the development of efficient, reliable, and environmentally safe electrochemical energy storage systems due to the ever-increasing global energy storage demand. Li ion battery systems have been used as the primary energy storage device over the last three decades. However, low abundance and uneven distribution of lithium and cobalt in the earth crust and the associated cost of these materials, have resulted in a concerted effort to develop beyond lithium electrochemical storage systems. In the case of non-Li ion rechargeable systems, the development of electrode materials is a significant challenge, considering the larger ionic size of the metal-ions and slower kinetics. Two-dimensional(2D) materials, such as graphene, transition metal dichalcogenides, MXenes and phosphorene, have garnered significant attention recently due to their multi-faceted advantageous properties: large surface areas, high electrical and thermal conductivity, mechanical strength, etc. Consequently, the study of 2D materials as negative electrodes is of notable importance as emerging non-Li battery systems continue to generate increasing attention. Among these interesting materials, graphene has already been extensively studied and reviewed, hence this report focuses on 2D materials beyond graphene for emerging non-Li systems. We provide a comparative analysis of 2D material chemistry, structure, and performance parameters as anode materials in rechargeable batteries and supercapacitors.展开更多
Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its i...Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its insufficient cathode capacity,calling for a newly developed working mechanism.In addition,an irregular constant increase of the cathode capacity was always observed during cycling,but cannot be explained based on the current understanding.Here,we observed an increase of specific capacity by 60%with stable Coulombic efficiency of 98%during 7000 cycles life of Al-graphene batteries employing AlCl3/ET3NHCl electrolyte.We demonstrated this growing cathode capacity is attributed to an increasing contribution of capacitive charge storage during cycling,because a gradually enlarged surface area as capacitive active sites is enabled by the exfoliation of graphitic cathode during the periodic intercalation process.Moreover,the graphene cathode was exfoliated more significantly in AlCl3/ET3NHCl than 1-ethyl-3-methylimidazolium chloride-based electrolyte,which results from the heavier stress on the graphene layers caused by the larger intercalants in AlCl3/ET3NHCl.The common intercalation of cations with AlCl4-clusters was therefore supposed to occur during charging.This new proposed mechanism can offer the new thought for future design on high-capacity cathode of Al-ion battery.展开更多
Ultrathin MoS2 nanosheets were prepared in high yield using a facile and effective hydrothermal intercalation and exfoliation route. The products were characterized in detail using X-ray diffraction, scanning electron...Ultrathin MoS2 nanosheets were prepared in high yield using a facile and effective hydrothermal intercalation and exfoliation route. The products were characterized in detail using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results show that the high yield of MoS2 nanosheets with good quality was successfully achieved and the dimensions of the immense nanosheets reached 1 μm-2/zm. As anode material for Li-ion batteries, the as-prepared MoS2 nanosheets electrodes exhibited a good initial capacity of 1190 mAh.g-l and excellent cyclic stability at constant current density of 50 mA.g-1. After 50 cycles, it still delivered reversibly sustained high capacities of 750 mAh.g-1.展开更多
With the discovery of graphene,black phosphorus(BP)has been rediscovered as a two-dimensional(2 D)layered material.Since its first preparation in 2014,2 D BP has elicited immense interest,and has exhibited excellent p...With the discovery of graphene,black phosphorus(BP)has been rediscovered as a two-dimensional(2 D)layered material.Since its first preparation in 2014,2 D BP has elicited immense interest,and has exhibited excellent properties,such as distinct pleated structures in layers,adjustable direct bandgap,high carrier mobility,moderate on/off ratio,large specific surface area,and various interesting in-layer anisotropies.However,the realization of these excellent properties depends on the preparation of highquality 2 D BP sheets.Electrochemical exfoliation methods are typically performed under mild conditions,thus,these methods are convenient,controllable,and can produce high-quality 2 D BP sheets.This review summarizes research progress in BP sheets preparation through anodic,cathodic,and electrolyte exfoliation in recent years.Different exfoliating methods affect the quality of 2 D BP sheets.Moreover,possible exfoliating mechanisms and the potential applications of different exfoliating methods are summarized and discussed in detail.Lastly,the shortcomings of existing research on electrochemical exfoliation are presented,and suggestions and prospects for future research on the electrochemical exfoliation of 2 D BP are proposed.展开更多
The effects of ethylene vinyl acetate copelymer (EVA) as a compatibilizer on the dispersion of organically modified montmorillonite(org-MMT) into low-density polyethylene(LDPE) during melt extrusion compounding ...The effects of ethylene vinyl acetate copelymer (EVA) as a compatibilizer on the dispersion of organically modified montmorillonite(org-MMT) into low-density polyethylene(LDPE) during melt extrusion compounding were studied. The X-ray diffraction patterns reveal that as compared with LDPE, EVA can intercalate more easily into the interlay gallery of org-MMT when the composites contain a low org-MMT content. Exfoliated LDPE/org-MMT nanocompesites in the presence of an EVA compatibilizer could be prepared by using a two-step melt compounding technique with a twin-screw extruder.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51872214 and 52172124)the Fundamental Research Funds for the Central Universities(WUT:2021Ⅲ019JC and 2018Ⅲ041GX)。
文摘Liquid-phase exfoliation was employed to synthesize Sr_(2)Nb_(3)O_(10) perovskite nanosheets with thicknesses down to 1.76 nm.Transmission electron microscopy(TEM),atomic force microscope(AFM),X-ray photoelectron spectrometer(XPS),and other characterization techniques were used to evaluate the atomic structure and chemical composition of the exfoliated nanosheets.A UV photodetector based on individual Sr_(2)Nb_(3)O_(10) nanosheets was prepared to demonstrate the application of an ultraviolet(UV) photodetector.The UV photodetector exhibited outstanding photocurrent and responsivity with a responsivity of 3×10^(5) A·W^(-1) at 5 V bias under 280 nm illumination,a photocurrent of 60 nA,and an on/off ratio of 3×10^(2).
文摘To screen patients with early cervical lesions by analyzing the infection of high-risk Human papillomavirus (HR-HPV). Research Methods: The cervical exfoliated cell specimens and their clinical data were collected. The HPV infection types of the collected specimens were detected by fluorescence quantitative PCR, and the correlation between HPV infection and clinicopathological features was analyzed statistically. Results: 725 cases were HR-HPV positive from 2605 cases, including 15 high-risk types of HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68. Different histological types ranged from NILM to HSIL, and the positive rate of HPV showed an increasing trend with the aggravation of cervical lesions. Conclusion: The positive rate of 15 high-risk HPV types in the collected specimens was 27.8%. Patients with early cervical lesions could be screened for 15 high-risk HPV infection types.
基金supported by the National Natural Science Foundation of China(22008221)Startup Research Fund of Zhengzhou University(32211716)+3 种基金Key Scientific Research Projects of Colleges and Universities in Henan Province(21A530005)Guangdong Basic and Applied Basic Research Foundation(2021A1515110789)Hunan Provincial Natural Science Foundation of China(2022JJ40431)Zhengzhou Collaborative Innovation Major Project。
文摘Spent cathode carbon(SCC)from aluminum electrolysis is a potential graphite resource.However,full use of the SCC remains a challenge,since it contains many hazardous substances(e.g.,fluoride salts,cyanides),encapsulated within the thick carbon layers and thus posing serious environmental concerns.This work presents a chemical oxidative exfoliation route to achieve the recycling of SCC and the decontaminated SCC with high-valued graphene oxide(GO)-like carbon structures(SCC-GO)is applied as an excellent adsorbent for organic pollutants.Specifically,after the oxidative exfoliation,the embedded hazardous constituents are fully exposed,facilitating their subsequent removal by aqueous leaching.Moreover,benefiting from the enhanced specific surface areas along with abundant O-containing functional groups,the as-produced SCC-GO,shows an adsorption capacity as high as 347 mg·g^(-1)when considering methylene blue as a pollutant model,which exceeds most of the recently reported carbon-based adsorbents.Our study provides a feasible solution for the efficient recycling of hazardous carbonaceous wastes.
基金financial support from the China Scholarship Council(CSC grant.201808330389)。
文摘MoS_(2) is a highly promising material for application in lithium-ion battery anodes due to its high theoretical capacity and low cost.However,problems with a fast capacity decay over cycling,especially at the first cycles,and poor rate performance have deterred its practical implementation.Herein,electrodes comprised solely of few-layers 2D MoS_(2) nanosheets have been manufactured by scalable liquid-phase exfoliation and spray deposition methods.The long-standing controversy questioning the reversibility of conversion processes of MoS_(2)-based electrodes was addressed.Raman studies revealed that,in 2D MoS_(2) electrodes,conversion processes are indeed reversible,where nanostructure played a key role.Cycling of the electrodes at high current rates revealed an intriguing phenomenon consisting of a continuously increasing capacity after ca.100-200 cycles.This phenomenon was comprehensively addressed by a variety of electrochemical and microscopy methods that revealed underlying physical activation mechanisms that involved a range of profound electrode structural changes.Activation mechanisms delivered a capacitive electrode of a superior rate performance and cycling stability,as compared to the corresponding pristine electrodes,and to MoS_(2) electrodes previously reported.Herein,we have devised a methodology to overcome the problem of cycling stability of 2D MoS_(2) electrodes.Moreover,activation of electrodes constitutes a methodology that could be applied to enhance the energy storage performance of electrodes based on other 2D nanomaterials,or combinations thereof,strategically combining chemistries to engineer electrodes of superior energy storage properties.
基金supported by Huazhong University of Science and Technology(No.2021XXJS036,3004013134)National Natural Science Foundation of China(No.51903099,82002879,22102059)+2 种基金the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003)China Postdoctoral Science Foundation(2021M692475,2021T140524,XJ2021037)support from the 100 Talents Program of the Hubei Provincial Government。
文摘We report a new facile light-induced strategy to disperse micron-sized aggregated bulk covalent organic frameworks(COFs)into isolated COFs nanoparticles.This was achieved by a series of metal-coordinated COFs,namely COF-909-Cu,-Co or-Fe,where for the first time the diffusio-phoretic propulsion was utilized to design COF-based micro/nanomotors.The mechanism studies revealed that the metal ions decorated in the COF-909 backbone could promote the separation of electron and holes and trigger the production of sufficient ionic and reactive oxygen species under visible light irradiation.In this way,strong light-induced self-diffusiophoretic effect is achieved,resulting in good dispersion of COFs.Among them,COF-909-Fe showed the highest dispersion performance,along with a drastic decrease in particle size from 5μm to500 nm,within only 30 min light irradiation,which is inaccessible by using traditional magnetic stirring or ultrasonication methods.More importantly,benefiting from the outstanding dispersion efficiency,COF-909-Fe micro/nanomotors were demonstrated to be efficient in photocatalytic degradation of tetracycline,about 8 times faster than using traditional magnetic stirring method.This work opens up a new avenue to prepare isolated nanosized COFs in a high-fast,simple,and green manner.
基金the financial supports from the National Natural Science Foundation of China (No.U1704251 and 21733011)the National Key Research and Development Program of China (2017YFA0403101)+1 种基金Natural Science Foundation of Henan province (No.202300410220)the 111 Project (No.D17007)。
文摘Disulfide zirconium(ZrS_(2)) is a two-dimensional(2D) transition metal disulfide and has given rise to extensive attention because of its distinctive electronic structure and properties.However,mass production of high quality of ZrS_(2)nanosheets to realize their practical application remains a challenge.Here,we have successfully exfoliated the bulk ZrS_(2)powder with the thickness of micron into single and few-layer nanosheets through liquid-phase exfoliation in N-methylpyrrolidone(NMP) assisted via aliphatic amines as intercalators.It is found that the exfoliation yield is as high as 27.3%,which is the record value for the exfoliation of ZrS_(2)nanosheets from bulk ZrS_(2)powder,and 77.1% of ZrS_(2)nanosheets are 2-3 layers.The molecular geometric size and aliphatic amine basicity have important impact on the exfoliation.Furthermore,the ZrS_(2)nanosheets have been used as catalyst in the electrocatalytic dinitrogen reduction with the NH3yield of 57.75 μg h^(-1)mg_(cat.)^(-1),which is twice that by ZrS_(2)nanofibers reported in literature and three times that by the bulk ZrS_(2)powder.Therefore,the liquid phase exfoliation strategy reported here has great potential in mass production of ZrS_(2)nanosheets for high activity electrocatalysis.
基金financially supported by the National Natural Science Foundation of China(No.51775353)the National Key Research and Development Program of China(No.2019YFB2006501)+2 种基金the Program for Natural Science Foundation of Liaoning Province(No.2021-BS-150)Science and Technology Program of Liaoning Provincial Department of Education(LJKZ0116)Hebei Key Laboratory of Dielectric and Electrolyte Functional Material,Northeastern University at Qinhuangdao(HKDEFM2021204)。
文摘Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and corrosion resistance of U-shaped cooling channels made of Al-12Si alloy was examined in depth.The experimental results suggest that as the preheating temperature increased from 273 K to 573 K,the roughness of the inner wall of the cooling channel reduced from 96.6μm to 77.0μm.When the preheating temperature continued to increase to 723 K,the roughness increased to 85.3μm.The wetting between the Al melt and the carbon fiber will reduce micro bubbles and waves on the channel wall as the preheating temperature rises,thereby reducing the roughness.However,with the further increase of preheating temperature,it will increase the solidification time of the Al melt.At this time,the carbon fiber and Al melt will take more time to react,which increases the roughness of the channel wall to a certain extent.The results of exfoliation corrosion show that the larger roughness will aggravate exfoliation corrosion.The prolongation of high temperature reaction time between the carbon fiber and the Al melt will lead to the segregation of Si,which is easy to cause intergranular corrosion.Therefore,reasonable preheating temperature has an important impact on the roughness and corrosion resistance of U-shaped cooling channels.
基金financially supported by the UK Research Council EPSRC EP/009050/1。
文摘The doping of functionalized graphene oxide(GO)in the membranes becomes a promising method for improving the performance of high-temperature proton exchange membrane fuel cells(HT-PEMFC).Phosphonated graphene oxide(PGO)with a P/O ratio of 8.5%was quickly synthesised by one-step electrochemical exfoliation based on a three-dimensiaonal(3D)printed reactor and natural graphite flakes.Compared with the GO prepared by the two-step electrochemical exfoliation method,the PGO synthesized by the one-step electrochemical exfoliation can better improve the performance of the membrane-electrode-assembly(MEA)based on the polybenzimidazole(PBI)membrane in the HTPEMFC.The doping of 1.5 wt%GO synthesised by electrochemical exfoliation with the 2-step method or reactor method in PBI increased the peak power density by 17.4%or 35.4%compared to MEA based on pure PBI membrane at 150℃,respectively.In addition,the doping of PGO in PBI improves its durability under accelerated stress test(AST).
文摘Background: A subset of cancer is particularly vulnerable to hydration prior to chemotherapy protocols;however, real-world outcomes-based data on pre-hydration elements of patients with tumor is sparse. Case Presentations: This retrospective case series describes a cohort of adult patients with terminal stage cancer who were seen between July 1, 2023, and September 25, 2023 and underwent various chemotherapy protocols, which, to our knowledge, represents comprehensive analysis of this patient population. We performed a retrospective search of patients identifying 50 cases of the chemotherapies of patients with cancer and extracted the clinical data via individual chart reviews. At the time of diagnosis, 24 patients were prehydrated with NaCl with KCl prior to the chemotherapy against the tumor, and 26 patients were taking normal saline only before undergoing cancer-specific treatment. Hydration and, prior chemotherapeutic agents use were the most common predepositse. Carcinomatosis peritoneii were the most common signs of the terminal stage of cancer within patients. Twenty-four patients were admitted to the hospital and two received NaCl with KCl hydaration prior to the platinum based chemotherapeutic agent treatment. Twenty-six patients received only normal saline hydration. Conclusion: Our data suggest that NaCl with KCl prehydaration results in better prognosis, including reduced tumor burden or decreased lymph node invasion, when compared to other vulnerable patients populations that receive only normal saline hydration. The graphene exfoliation effect of NaCl with KCl may have contributed to these results.
文摘Guillain-Barré syndrome is a rare but fatal autoimmune disease of unknown origin. Infectious disease is the most common etiology of Guillain-Barré syndrome. We had a 75-year-old female patient with Guillain-Barré syndrome and a 90-year-old male patient with facial nerve palsy admitted to our hospital. Both patients experienced recovery from early Guillain-Barré syndrome and peripheral facial nerve palsy after receiving intravenous infusion of NaCl with KCl solution and taking vitamin C.
基金Supported by Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science,No.17K08966(to Ohkoshi S)
文摘Mesenchymal stem cells(MSCs) as a source for regenerative medicine are now the subject of much clinical attention. There are high expectations due to their safety, low tumorigenic risk, and low ethical concerns. MSC therapy has been approved for acute graft-versus host diseases since 2015. Tooth-derived MSCs are known to have a great potential in their proliferation and differentiation capacities, even when compared with bone-marrow-derived MSCs. In particular, stem cells from human exfoliated deciduous teeth(SHEDs) are the best candidates for personal cell banking(dental pulp cell bank), because they can be obtained less invasively in the natural process of individual growth. SHEDs are known to differentiate into hepatocytes. There have been several studies showing the effectiveness of SHEDs on the treatment of liver failure in animal models. They may exert their effects either by repopulation of cells in injured liver or by paracrine mechanisms due to their immuneregulatory functions. Moreover, it may be possible to use each individuals' dental pulp cells as a future source of tailor-made differentiated hepatocytes in the context of a bioartificial liver or liver-on-a-chip to screen for drug toxicity.
文摘AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been isolated 5 years ago from human exfoliated deciduous teeth. The undifferentiated stem cells were seeded into mandibular bone through-andthrough defects of 4 dogs. Similar defects in control group were filled with cell-free collagen scaffold. After 12 wk, biopsies were taken and morphometric analysis was performed. The percentage of new bone formation and foreign body reaction were measured in each case. The data were subject to statistical analysis using the Mann-Whitney U and Kruskalwalis statistical tests. Differences at P < 0.05 was considered as significant level.RESULTS: There were no significant differences between control and SHED-seeded groups in connective tissue(P = 0.248), woven bone(P = 0.248) and compact bone(P = 0.082). There were not any side effects in transplanted SHED group such as teratoma or malignancy and abnormalities in this period.CONCLUSION: SHEDs which had been isolated and characterized 5 years ago and stored with cryopreservation banking were capable of proliferation and osteogenesis after 5 years, and no immune response was observed after three months of seeded SHEDs.
文摘The corrosion behavior of an Al-6Mg-Sc-Zr alloy was studied and compared with that of an Al-6Mg-Zr alloy. The addition of scandium into the Al-6Mg-Zr alloy reduced the susceptibility to exfoliation corrosion. By using the constant load tensile method in a 3.5 wt.% NaCl solution, the resistance to SCC of the Al-6Mg-Sc-Zr alloy was higher than that of the Al-6Mg-Zr alloy. When the specimens were not applied with an anodic current, the Al-6Mg-Sc-Zr alloy was resistance to SCC and no brittle cracking was found on the fracture surface. When an anodic current was applied, the Al-6Mg-Sc-Zr alloy specimens failed as a result of accelerated corrosion rather than SCC. It was believed that the addition of scandium re- sulted in (Al3Sc, Zr) particles that greatly refined grains and promoted the formation of homogeneous discontinuous distribution of β-phase in the alloy base, which much contributed to good corrosion resistance of the Al-6Mg-Sc-Zr alloy.
基金financially supported by the National Natural Science Foundation of China(No.21503116)The Taishan Scholars Program of Shandong Province(No.tsqn20161004)the Youth1000 Talent Program of China
文摘The direct coating of graphene sheets obtained by electrochemical exfoliation on commercial paper renders the preparation of highly conductive flexible paper substrate for subsequent deposition of polyaniline (PANi) nanorods via electrochemical polymerization. The deposit ion of PANi can be well-controlled by adjusting the electrochemical polymerization time, leading to the formation of PANi coated graphene paper (PANi-GP). The as-prepared electrode exhibited high areal capacitance of 176 mF cm^-2 in three-electrode system at a current density of 0.2 mA cm^-2 which is around 10 times larger than that of pris-tine graphene paper due to the pseudocapacitive behavior of PANi. In-situ Raman test was used to determine the molecular changes during redox process of PANi. More importantly, all-solid-state symmetric capacitor assembled with two PANi-GP electrodes in a polymer electrolyte delivered an areal capacitanee of 123 mF cm^-2, corresponding to an areal energy density of 17.1 μWh cm^-2 and an areal power density of 0.25 mW cm^-2. The symmetric capacitor held a capacitive retention of 74.8% after 500 bending tests from 0 to 120°, suggesting the good flexibility and mechanical stability. These results showed the great promising application in flexible energy-storage devices.
基金supported by the National Science Foundation Grant Number 1454151
文摘Intensive research effort is currently focused on the development of efficient, reliable, and environmentally safe electrochemical energy storage systems due to the ever-increasing global energy storage demand. Li ion battery systems have been used as the primary energy storage device over the last three decades. However, low abundance and uneven distribution of lithium and cobalt in the earth crust and the associated cost of these materials, have resulted in a concerted effort to develop beyond lithium electrochemical storage systems. In the case of non-Li ion rechargeable systems, the development of electrode materials is a significant challenge, considering the larger ionic size of the metal-ions and slower kinetics. Two-dimensional(2D) materials, such as graphene, transition metal dichalcogenides, MXenes and phosphorene, have garnered significant attention recently due to their multi-faceted advantageous properties: large surface areas, high electrical and thermal conductivity, mechanical strength, etc. Consequently, the study of 2D materials as negative electrodes is of notable importance as emerging non-Li battery systems continue to generate increasing attention. Among these interesting materials, graphene has already been extensively studied and reviewed, hence this report focuses on 2D materials beyond graphene for emerging non-Li systems. We provide a comparative analysis of 2D material chemistry, structure, and performance parameters as anode materials in rechargeable batteries and supercapacitors.
基金supported by the National Natural Science Foundation of China(No.51533008)National Key R&D Program of China(No.2016YFA0200200)+1 种基金Key Research and Development Plan of Zhejiang Province(2018C01049)Fujian Provincial Science and Technology Major Projects(No.2018HZ0001-2)。
文摘Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its insufficient cathode capacity,calling for a newly developed working mechanism.In addition,an irregular constant increase of the cathode capacity was always observed during cycling,but cannot be explained based on the current understanding.Here,we observed an increase of specific capacity by 60%with stable Coulombic efficiency of 98%during 7000 cycles life of Al-graphene batteries employing AlCl3/ET3NHCl electrolyte.We demonstrated this growing cathode capacity is attributed to an increasing contribution of capacitive charge storage during cycling,because a gradually enlarged surface area as capacitive active sites is enabled by the exfoliation of graphitic cathode during the periodic intercalation process.Moreover,the graphene cathode was exfoliated more significantly in AlCl3/ET3NHCl than 1-ethyl-3-methylimidazolium chloride-based electrolyte,which results from the heavier stress on the graphene layers caused by the larger intercalants in AlCl3/ET3NHCl.The common intercalation of cations with AlCl4-clusters was therefore supposed to occur during charging.This new proposed mechanism can offer the new thought for future design on high-capacity cathode of Al-ion battery.
基金supported by the Grants from National Natural Science Foundation of China(No.51172191,51002129 and 11074211)the National Basic Research Program of China(2012CB921303)the Hunan Provincial Innovation Foundation for Graduate(No.CX2012B265)
文摘Ultrathin MoS2 nanosheets were prepared in high yield using a facile and effective hydrothermal intercalation and exfoliation route. The products were characterized in detail using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results show that the high yield of MoS2 nanosheets with good quality was successfully achieved and the dimensions of the immense nanosheets reached 1 μm-2/zm. As anode material for Li-ion batteries, the as-prepared MoS2 nanosheets electrodes exhibited a good initial capacity of 1190 mAh.g-l and excellent cyclic stability at constant current density of 50 mA.g-1. After 50 cycles, it still delivered reversibly sustained high capacities of 750 mAh.g-1.
基金financially supported by the Youth talent support program of science and technology association of colleges of Shaanxi Province(Grant No.20190609)the Special scientific research plan of education department of Shaanxi province(Grant No.19JK0190 and 19JK0186)+3 种基金the Natural Science Foundation of Shaanxi Province(Grant No.2019JM508)the Open project of Key laboratory of catalytic foundation and application of Shaanxi province(Grant No.SLGPT2019KF01-23)the Opening Foundation of Shaanxi Key Laboratory of Industrial Automation(No.SLGPT2019KF01-10)the School-level project of Shaanxi University of Technology(Grant No.SLGRC03,SLGRC02)。
文摘With the discovery of graphene,black phosphorus(BP)has been rediscovered as a two-dimensional(2 D)layered material.Since its first preparation in 2014,2 D BP has elicited immense interest,and has exhibited excellent properties,such as distinct pleated structures in layers,adjustable direct bandgap,high carrier mobility,moderate on/off ratio,large specific surface area,and various interesting in-layer anisotropies.However,the realization of these excellent properties depends on the preparation of highquality 2 D BP sheets.Electrochemical exfoliation methods are typically performed under mild conditions,thus,these methods are convenient,controllable,and can produce high-quality 2 D BP sheets.This review summarizes research progress in BP sheets preparation through anodic,cathodic,and electrolyte exfoliation in recent years.Different exfoliating methods affect the quality of 2 D BP sheets.Moreover,possible exfoliating mechanisms and the potential applications of different exfoliating methods are summarized and discussed in detail.Lastly,the shortcomings of existing research on electrochemical exfoliation are presented,and suggestions and prospects for future research on the electrochemical exfoliation of 2 D BP are proposed.
文摘The effects of ethylene vinyl acetate copelymer (EVA) as a compatibilizer on the dispersion of organically modified montmorillonite(org-MMT) into low-density polyethylene(LDPE) during melt extrusion compounding were studied. The X-ray diffraction patterns reveal that as compared with LDPE, EVA can intercalate more easily into the interlay gallery of org-MMT when the composites contain a low org-MMT content. Exfoliated LDPE/org-MMT nanocompesites in the presence of an EVA compatibilizer could be prepared by using a two-step melt compounding technique with a twin-screw extruder.