In this work we report that after single-walled carbon nanotubes(SWNTs) are sheared with a pair of titanium scissors,the magnetization becomes larger than that of the corresponding pristine ones. The magnetization inc...In this work we report that after single-walled carbon nanotubes(SWNTs) are sheared with a pair of titanium scissors,the magnetization becomes larger than that of the corresponding pristine ones. The magnetization increases proportionally with the number of SWNTs with sheared ends, suggesting that there exist magnetic moments at the sheared ends of SWNTs.By using the coefficient of this linear relation, the average magnetic moment is estimated to be 41.5 ± 9.8 μB(Bohr magneton) per carbon atom in the edge state at temperature of 300.0 K, suggesting that ultrahigh magnetic fields can be produced. The dangling sigma and pi bonds of the carbon atoms at sheared ends play important roles in determining the unexpectedly high magnetic moments, which may have great potential applications.展开更多
A Van Hove singularity(VHS) is a singularity in the phonon or electronic density of states of a crystalline solid. When the Fermi energy is close to the VHS, instabilities will occur, which can give rise to new phases...A Van Hove singularity(VHS) is a singularity in the phonon or electronic density of states of a crystalline solid. When the Fermi energy is close to the VHS, instabilities will occur, which can give rise to new phases of matter with desirable properties. However, the position of the VHS in the band structure cannot be changed in most materials. In this work, we demonstrate that the carrier densities required to approach the VHS are reached by gating in a suspended carbon nanotube Schottky barrier transistor. Critical saddle points were observed in regions of both positive and negative gate voltage, and the conductance flattened out when the gate voltage exceeded the critical value. These novel physical phenomena were evident when the temperature is below 100 K. Further, the temperature dependence of the electrical characteristics was also investigated in this type of Schottky barrier transistor.展开更多
BACKGROUND Endometriosis affects approximately 10%of reproductive-age women,however,endometriosis associated malignant transformation is rare and is often report as a rare case.CASE SUMMARY Herein,we report of a 49-ye...BACKGROUND Endometriosis affects approximately 10%of reproductive-age women,however,endometriosis associated malignant transformation is rare and is often report as a rare case.CASE SUMMARY Herein,we report of a 49-year-old female patient who suffered from severe left lower abdominal pain and imaging examination revealed an irregular mass in the left iliac fossa.Histopathological examination revealed main undifferentiated adenocarcinoma with a few typical endometrial epithelial and stromal tissues in the adjacent area.Combined with the immunohistochemical staining and the negative intra-or postoperative results from exploratory laparotomy,gastroscopy,enteroscopy and positron emission tomography,the tumor was considered to be derived from endometriosis.The patient underwent hysterectomy,bilateral salpingectomy,bilateral ovariectomy,and multipoint biopsy of the pelvic peritoneum.Subsequent radiotherapy and chemotherapy were performed.The patient recovered well post-operation and there was no evidence of recurrence after 10 mo of follow-up via computed tomography and magnetic resonance imaging.CONCLUSION This case highlights a rare presentation of mass-like extragonadal endometriosis associated malignant transformation in the pelvis.Endometriosis associated malignant transformation is rare and difficult to diagnose in clinical settings,with diagnoses depending on pathological results and the exclusion of metastasis from other organs.Fortunately,patients are often diagnosed at younger ages,as well as at early stages;thus they generally have relatively favorable prognoses.展开更多
Through the establishment of music teaching effect evaluation model and the multimedia courseware evaluation model, which can effectively avoid the influence of subjective evaluation, the evaluation process will be si...Through the establishment of music teaching effect evaluation model and the multimedia courseware evaluation model, which can effectively avoid the influence of subjective evaluation, the evaluation process will be simple and objective. Through the issuance of assessment questionnaire, each index is divided into four grades of excellent, good, poor, according to percentile scoring, the score of every index multiply corresponding weight, and then addition, and finally we can obtain the evaluation results.展开更多
The multi-media music teaching is to make video projector, video display, computer, TV, video order, CD, VCD, booth, acoustics, teaching software, and other media become an organic whole, and it is the floorboard of t...The multi-media music teaching is to make video projector, video display, computer, TV, video order, CD, VCD, booth, acoustics, teaching software, and other media become an organic whole, and it is the floorboard of the modem teaching equipment. Multimedia technology takes advantages of media combination including text, images, animation, sound that can hold information, it provides variegated and multidimensional teaching information space for the music teaching by the form of text, sound, music and so on, it makes the teaching content and mode of music teaching better improvement and enrichment, and it provides the technical support for music education modernization, and it is a new technology which is introduced into the field of teaching in recent years. Mastering the function of multimedia teaching as soon as possible and applying it effectively to music classroom teaching is the need of modem education reform and development.展开更多
To further improve the biocompatibility of polyurethanes,a new lysine 2-(2-aminoethoxy)ethanol phosphatidylcholine(LAPC)is synthesized to use as chain extender for preparing a series of phosphatidylcholine polyurethan...To further improve the biocompatibility of polyurethanes,a new lysine 2-(2-aminoethoxy)ethanol phosphatidylcholine(LAPC)is synthesized to use as chain extender for preparing a series of phosphatidylcholine polyurethanes(PCPUs).Poly(e-caprolactone)(PCL)and poly(ethylene glycol)(PEG)are used as soft segments,and L-lysine ethyl ester diisocyanate(LDI),LAPC and L-lysine are used as hard segments.The obtained PCPUs exhibit appropriate mechanical properties with break elongation of 1000–1700%,tensile strength of 7–22 MPa,and relatively high elastic modulus of 11–18 MPa,which could admirably satisfy the requirement for soft tissue engineering scaffolds.The phosphatidylcholine structures can increase the hydrophilicity of PCPU surfaces,which effectively reduce protein adsorption and platelet adhesion while promoting the cell proliferation.In addition,the LAPC chain extender,PCPU films and ultimate degradation products of PCPUs are proved to be nontoxic in cytotoxicity test.More interestingly,the cytokine release test of macrophages manifests that both LAPC and PCPU degradation products could effectively improve the proliferation of macrophages and induce them into a wound-healing phenotype.Thus,the obtained PCPUs have greatly potential applications of soft tissue engineering scaffolds for tissue repair and wound healing.展开更多
The size and density of Ag nanoparticles on n-layer MoS2 exhibit thickness- dependent behavior. The size and density of these particles increased and decreased, respectively, with increasing layer number （n） of n-la...The size and density of Ag nanoparticles on n-layer MoS2 exhibit thickness- dependent behavior. The size and density of these particles increased and decreased, respectively, with increasing layer number （n） of n-layer MoS2. Furthermore, the surface-enhanced Raman scattering （SERS） of Ag on this substrate was observed. The enhancement factor of this scattering varied with the thickness of MoS2. The mechanisms governing the aforementioned thickness dependences are proposed and discussed.展开更多
In recent years,two-dimensional(2D)ternary materials have attracted wide attention due to their novel properties which can be achieved by regulating their chemical composition with a very great degree of freedom and a...In recent years,two-dimensional(2D)ternary materials have attracted wide attention due to their novel properties which can be achieved by regulating their chemical composition with a very great degree of freedom and adjustable space.However,as for the precise synthesis of 2D ternary materials,great challenges still lie ahead that hinder their further development.In this work,we demonstrated a simple and reliable approach to synthesize 2D ternary-layered BiOCl crystals through a microwave-assisted space-confined process in a short time(<3 minutes).Their ultraviolet(UV)detection performance was analyzed systematically.The photodetectors based on the as-obtained BiOCl platelets demonstrate high sensitivity to 266-nm laser illumination.The responsivity is calculated to be8 A/W and the response time is up to be18 ps.On the other hand,the device is quite stable after being exposed in the ambient air within 3 weeks and the response is almost unchanged during the measurement.The facile and fast synthesis of single crystalline BiOCl platelets and its high sensitivity to UV light irradiation indicate the potential optoelectronic applications of 2D BiOCl photodetectors.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2018YFA0208403 and 2016YFA0200403)the National Natural Science Foundation of China(Grant Nos.51472057,11874129,91323304,and 11674387)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA09040101)the Baotou Rare Earth Research and Development Centre,Chinese Academy of Sciences(Grant No.GZR 2018001)
文摘In this work we report that after single-walled carbon nanotubes(SWNTs) are sheared with a pair of titanium scissors,the magnetization becomes larger than that of the corresponding pristine ones. The magnetization increases proportionally with the number of SWNTs with sheared ends, suggesting that there exist magnetic moments at the sheared ends of SWNTs.By using the coefficient of this linear relation, the average magnetic moment is estimated to be 41.5 ± 9.8 μB(Bohr magneton) per carbon atom in the edge state at temperature of 300.0 K, suggesting that ultrahigh magnetic fields can be produced. The dangling sigma and pi bonds of the carbon atoms at sheared ends play important roles in determining the unexpectedly high magnetic moments, which may have great potential applications.
基金supported by National Science Foundation of China (Grant No. 51472057)the Major Nanoprojects of Ministry of Science and Technology of China (2016YFA0200403)
文摘A Van Hove singularity(VHS) is a singularity in the phonon or electronic density of states of a crystalline solid. When the Fermi energy is close to the VHS, instabilities will occur, which can give rise to new phases of matter with desirable properties. However, the position of the VHS in the band structure cannot be changed in most materials. In this work, we demonstrate that the carrier densities required to approach the VHS are reached by gating in a suspended carbon nanotube Schottky barrier transistor. Critical saddle points were observed in regions of both positive and negative gate voltage, and the conductance flattened out when the gate voltage exceeded the critical value. These novel physical phenomena were evident when the temperature is below 100 K. Further, the temperature dependence of the electrical characteristics was also investigated in this type of Schottky barrier transistor.
文摘BACKGROUND Endometriosis affects approximately 10%of reproductive-age women,however,endometriosis associated malignant transformation is rare and is often report as a rare case.CASE SUMMARY Herein,we report of a 49-year-old female patient who suffered from severe left lower abdominal pain and imaging examination revealed an irregular mass in the left iliac fossa.Histopathological examination revealed main undifferentiated adenocarcinoma with a few typical endometrial epithelial and stromal tissues in the adjacent area.Combined with the immunohistochemical staining and the negative intra-or postoperative results from exploratory laparotomy,gastroscopy,enteroscopy and positron emission tomography,the tumor was considered to be derived from endometriosis.The patient underwent hysterectomy,bilateral salpingectomy,bilateral ovariectomy,and multipoint biopsy of the pelvic peritoneum.Subsequent radiotherapy and chemotherapy were performed.The patient recovered well post-operation and there was no evidence of recurrence after 10 mo of follow-up via computed tomography and magnetic resonance imaging.CONCLUSION This case highlights a rare presentation of mass-like extragonadal endometriosis associated malignant transformation in the pelvis.Endometriosis associated malignant transformation is rare and difficult to diagnose in clinical settings,with diagnoses depending on pathological results and the exclusion of metastasis from other organs.Fortunately,patients are often diagnosed at younger ages,as well as at early stages;thus they generally have relatively favorable prognoses.
文摘Through the establishment of music teaching effect evaluation model and the multimedia courseware evaluation model, which can effectively avoid the influence of subjective evaluation, the evaluation process will be simple and objective. Through the issuance of assessment questionnaire, each index is divided into four grades of excellent, good, poor, according to percentile scoring, the score of every index multiply corresponding weight, and then addition, and finally we can obtain the evaluation results.
文摘The multi-media music teaching is to make video projector, video display, computer, TV, video order, CD, VCD, booth, acoustics, teaching software, and other media become an organic whole, and it is the floorboard of the modem teaching equipment. Multimedia technology takes advantages of media combination including text, images, animation, sound that can hold information, it provides variegated and multidimensional teaching information space for the music teaching by the form of text, sound, music and so on, it makes the teaching content and mode of music teaching better improvement and enrichment, and it provides the technical support for music education modernization, and it is a new technology which is introduced into the field of teaching in recent years. Mastering the function of multimedia teaching as soon as possible and applying it effectively to music classroom teaching is the need of modem education reform and development.
基金This work was supported by the National Natural Science Foundation of China(51273124,51333003 and 51573114)the National Science Fund for Distinguished Young Scholars of China(51425305).
文摘To further improve the biocompatibility of polyurethanes,a new lysine 2-(2-aminoethoxy)ethanol phosphatidylcholine(LAPC)is synthesized to use as chain extender for preparing a series of phosphatidylcholine polyurethanes(PCPUs).Poly(e-caprolactone)(PCL)and poly(ethylene glycol)(PEG)are used as soft segments,and L-lysine ethyl ester diisocyanate(LDI),LAPC and L-lysine are used as hard segments.The obtained PCPUs exhibit appropriate mechanical properties with break elongation of 1000–1700%,tensile strength of 7–22 MPa,and relatively high elastic modulus of 11–18 MPa,which could admirably satisfy the requirement for soft tissue engineering scaffolds.The phosphatidylcholine structures can increase the hydrophilicity of PCPU surfaces,which effectively reduce protein adsorption and platelet adhesion while promoting the cell proliferation.In addition,the LAPC chain extender,PCPU films and ultimate degradation products of PCPUs are proved to be nontoxic in cytotoxicity test.More interestingly,the cytokine release test of macrophages manifests that both LAPC and PCPU degradation products could effectively improve the proliferation of macrophages and induce them into a wound-healing phenotype.Thus,the obtained PCPUs have greatly potential applications of soft tissue engineering scaffolds for tissue repair and wound healing.
文摘The size and density of Ag nanoparticles on n-layer MoS2 exhibit thickness- dependent behavior. The size and density of these particles increased and decreased, respectively, with increasing layer number （n） of n-layer MoS2. Furthermore, the surface-enhanced Raman scattering （SERS） of Ag on this substrate was observed. The enhancement factor of this scattering varied with the thickness of MoS2. The mechanisms governing the aforementioned thickness dependences are proposed and discussed.
基金National Research Foundation Singapore,Grant/Award Numbers:AStar QTE program.,AcRF Tier 2 MOE2017-T2-2-002,MOE Tier 2 MOE2015-T2-2-007,MOE Tier 3 MOE2018-T3-1-002,MOE2016-T2-2-153,MOE2017-T2-2-136,NRF-RF2013-08.MOE Tier 1 RG7/18,NRF2017-NRF-ANR0022DPSNatural Science Foundation of Jiangsu Province,Grant/Award Number:BK20160994+1 种基金This work was supported by the Singapore National Research Foundation under NRF RF Award No.NRF-RF2013-08.MOE Tier 1 RG7/18,MOE Tier 2 MOE2015-T2-2-007,MOE2016-T2-2-153,MOE2017-T2-2-136,MOE Tier 3 MOE2018-T3-1-002,AcRF Tier 2 MOE2017-T2-2-002,NRF2017-NRF-ANR0022DPS,and A*Star QTE program.Dan Tian thanks the National Nature Science Foundation of China(Grant No.21601086)the Natural Science Foundation of Jiangsu Province(BK20160994)for financial support.
文摘In recent years,two-dimensional(2D)ternary materials have attracted wide attention due to their novel properties which can be achieved by regulating their chemical composition with a very great degree of freedom and adjustable space.However,as for the precise synthesis of 2D ternary materials,great challenges still lie ahead that hinder their further development.In this work,we demonstrated a simple and reliable approach to synthesize 2D ternary-layered BiOCl crystals through a microwave-assisted space-confined process in a short time(<3 minutes).Their ultraviolet(UV)detection performance was analyzed systematically.The photodetectors based on the as-obtained BiOCl platelets demonstrate high sensitivity to 266-nm laser illumination.The responsivity is calculated to be8 A/W and the response time is up to be18 ps.On the other hand,the device is quite stable after being exposed in the ambient air within 3 weeks and the response is almost unchanged during the measurement.The facile and fast synthesis of single crystalline BiOCl platelets and its high sensitivity to UV light irradiation indicate the potential optoelectronic applications of 2D BiOCl photodetectors.
