In the original publication,incorrect version of Corresponding authors has been published.You-Yuan Huang and Bo Wang should be corresponding authors.The corrected Correspondingg authors are provided in this correction.
This article discussed the mechanisms and precautions of abdominal acupuncture from three different perspectives. First, the relationship between Shénquè （神阙 CV 8） and zang-fu and eight extra meridians s...This article discussed the mechanisms and precautions of abdominal acupuncture from three different perspectives. First, the relationship between Shénquè （神阙 CV 8） and zang-fu and eight extra meridians stated in the ancient literature explained that the theory of CV 8 as the theoretical core of abdominal acupuncture therapy had literature support and theoretical evidence; second, with emphasis on the diagnosis and treatment based on differentiation of syndromes, four methods for selecting the points, including the ones according to hologram, meridians and collaterals, the Ba-kuo （八 廓） and three energizer, meanwhile, the origin of method selecting the points according to Three Energizer and clinical experience was also addressed; third, some problems about the manipulation of abdominal acupuncture therapy were put forward, such as selection of depth, direction, needle tool, as well as personal ideas and precautions, in order to ensure the clinical effect.展开更多
Distinction between Crohn's disease of the colonrectum and ulcerative colitis or inflammatory bowel disease(IBD) type unclassified can be of pivotal importance for a tailored clinical management,as each entity oft...Distinction between Crohn's disease of the colonrectum and ulcerative colitis or inflammatory bowel disease(IBD) type unclassified can be of pivotal importance for a tailored clinical management,as each entity often involves specific therapeutic strategies and prognosis.Nonetheless,no gold standard is available and the uncertainty of diagnosis may frequently lead to misclassification or repeated examinations.Hence,we have performed a literature search to address the problem of differential diagnosis in IBD colitis,revised current and emerging diagnostic tools and refined disease classification strategies.Nowadays,the differential diagnosis is an untangled issue,and the proper diagnosis cannot be reached in up to 10% of patients presenting with IBD colitis.This topic is receiving emerging attention,as medical therapies,surgical approaches and leading prognostic outcomes require more and more disease-specific strategies in IBD patients.The optimization of standard diagnostic approaches based on clinical features,biomarkers,radiology,endoscopy and histopathology appears to provide only marginal benefits.Conversely,emerging diagnostic techniques in the field of gastrointestinal endoscopy,molecular pathology,genetics,epigenetics,metabolomics and proteomics have already shown promising results.Novel advanced endoscopic imaging techniques and biomarkers can shed new light for the differential diagnosis of IBD,better reflecting diverse disease behaviors based on specific pathogenic pathways.展开更多
OBJECTIVE: To evaluate the reporting quality of randomized controlled trials(RCT) that compared Bo's abdominal acupuncture with conventional body acupuncture, and compare the efficacy and safetybetweenthembyperfor...OBJECTIVE: To evaluate the reporting quality of randomized controlled trials(RCT) that compared Bo's abdominal acupuncture with conventional body acupuncture, and compare the efficacy and safetybetweenthembyperforminga Meta-analysis.METHODS: All RCTs comparing Bo's abdominalacupuncture with conventional body acupuncture were included. English and Chinese databases were searched from their respective inceptions to March 2014. The reporting quality was assessed according to the "Consolidated Standards of Reporting Trials"(CONSORT) checklist for parallel RCTs and the revised "Standards for Reporting Interventions in Clinical Trials of Acupuncture"(STRICTA). A Meta-analysis was conducted to synthesize the effect sizes,and publication bias was evaluated by the Egger linear regression test using Stata.RESULTS: Ninety-seven studies were included, of which most lacked adequate reporting information, and 80.4% showed that the efficacy of abdominal acupuncture is superior to conventional body acupuncture, especially for the following diseases:lumbar disc herniation, cervical spondylosis, omarthritis and cervical vertigo, except simple obesity.Effect-sizes were controversial when evaluating different outcomes.CONCLUSION: The international standard CONSORT statement and STRICTA guidelines should be strictly applied when reporting acupuncture RCTs in the future. Abdominal acupuncture appears to be more effective compared with conventional body acupuncture for some diseases. However, further high quality blind RCTs using validated outcomeindexesandstandardreportingarewarranted.展开更多
OBJECTIVE:To investigate the effect of Bo′s abdominal acupuncture(BOAA)on fibroblast growth factor 21(FGF21)and its related adipokines in type 2 diabetes mellitus(T2DM)rats.METHODS:This study established obese T2DM r...OBJECTIVE:To investigate the effect of Bo′s abdominal acupuncture(BOAA)on fibroblast growth factor 21(FGF21)and its related adipokines in type 2 diabetes mellitus(T2DM)rats.METHODS:This study established obese T2DM rat model by high-fat diet(HFD)with a dose of streptozotocin(STZ,30 mg/kg).Obese T2DM rats were randomly subdivided into four groups(n=10):negative,BOAA,conventional acupuncture(COA group)and metformin group(Met group)groups.The biochemical parameters,mRNAs,and proteins were analyzed using enzyme-lined immunoassays kits,quantitative polymerase chain reaction and Western blot.RESULTS:Treatment with BOAA attenuated the histopathological changes in visceral fat and restored the alterations in the levels of body weight,fasting blood glucose(FBG),homeostasis model assessment for insulin resistance(HOMA-IR).BOAA treatment significantly decreased the levels of triglyceride,total cholesterol,low density lipoprotein cholesterol,leptin,and increased the serum levels of high-density lipoprotein cholesterol,fibroblast growth factor 21(FGF21),adiponectin(ADP),peroxisome proliferator-activated receptorγ(PPAR-γ),C-peptide(C-P)in obese T2DM rats.Furthermore,BOAA treatment significantly increased the mRNA expressions of FGF21,ADP,leptin,PPAR-γ,PPAR-αand adenosine 5‘-monophosphate(AMP)-activated protein kinase(AMPK).Besides,BOAA treatment upregulated the protein expressions of fibroblast growth factor receptors3(FGFR3),PPAR-α,extracellular signal-regulated kinase(ERK),phosphorylated ERK(p-ERK),AMPK,p-AMPK,Liver kinase B1(LKB1),phosphorylated LKB1(p-LKB1),acetyl-CoA carboxylase(ACC)and phosphorylated ACC(p-ACC),while downregulated the protein expressions of FGF21 and PPAR-γin visceral fat.CONCLUSIONS:BOAA treatment reduced FBG and body weight,and improved insulin sensitivity through regulating FGF21 signaling pathway and its related adipokine in obese T2DM rats.展开更多
The VUV-UV spectroscopic properties of Ce3＋ in Ba2Mg（BO3）2,Ba2Ca（BO3）2 and Sr2Mg（BO3）2 were compared,and the relation between the energy of the 4f→5d transition of Ce3＋ and the coordination environments of su...The VUV-UV spectroscopic properties of Ce3＋ in Ba2Mg（BO3）2,Ba2Ca（BO3）2 and Sr2Mg（BO3）2 were compared,and the relation between the energy of the 4f→5d transition of Ce3＋ and the coordination environments of substituted alkaline earth ions was discussed.The chromaticity coordinates of Ce3＋ activated X2Z（BO3）2（X=Ba,Sr;Z=Ca,Mg） phosphors were changeable from blue to whitish and further to green range by varying the doping concentration of Ce3＋ or the types of substituted alkaline earth ions upon 172 nm excitation.展开更多
The structure of LiSrY2（BO3）3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1（No.164）.The cell paramete...The structure of LiSrY2（BO3）3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1（No.164）.The cell parameters at room temperature are as follows：a = 10.3345（9）,c = 6.4049（11） ,V = 592.41（13） 3,Z = 3,Mr = 448.81,F（000） = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B（2） atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2（BO3）3 and photoluminescence properties of the Eu3＋ doped LiSrY2（BO3）3 were also studied.展开更多
The (Y,Gd)BO3:Tb3+ and Li+-doped (Y,Gd)BO3:Tb3+ phosphors were prepared by high temperature solid-state method. The inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning ...The (Y,Gd)BO3:Tb3+ and Li+-doped (Y,Gd)BO3:Tb3+ phosphors were prepared by high temperature solid-state method. The inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning electron microscopy (SEM), and the excitation and emission spectra were used to characterize the samples. The results of ICP-AES and XRD indicated that Li+ ions could enter the (Y,Gd)BO3:Tb3+ lattice and induce the lattice expansion. It could be seen from SEM that the particles were spherical a...展开更多
The {0001} face develops on the habit of self-frequency doubling laser crystal Yb: YAI3(B03)4 (YbYAB) only under high growth rate condition, and its morphology is rough. To study the growth mechanism of {0001} face, w...The {0001} face develops on the habit of self-frequency doubling laser crystal Yb: YAI3(B03)4 (YbYAB) only under high growth rate condition, and its morphology is rough. To study the growth mechanism of {0001} face, we have observed the growth morphology on {0001} polishing section by atomic force microscopy (AFM). A series of AFM images captured in different growth durations on the {0001} polishing section reflect the crystal growth process. It is shown that the growth morphology on the {0001} polishing section was rough with many hillocks at the first growth stage, and it can become smooth finally, although the growth morphology on the {0001} face developed naturally on YbYAB crystal habit is always rough. On the smooth {0001} surface formed at the last growth stage, there are some triangular pits. This fact is different from that of hillocks in most crystal growth morphologies. AFM can easily distinguish the pits or hillocks on the surface, but differential interfere contrast microscopy (DIC) can not do. The orientation of the triangular pits is just the opposite to the triangular {0001} faces. The chemical etching pattern is also composed of this kind of triangular pits. These growth morphology and etching pattern of the {0001} faces show 3m symmetry, but the point group of YbYAB crystal is 32. The symmetric contradiction between morphology and point group does not exist for quartz, although which has the same point group as YbYAB. From quartz {0001} surface morphology we can distinguish the right form or left form of the crystal, but from YbYAB {0001} surface morphology we can not do. The reason for the symmetric contradiction between YbYAB {0001} surface morphology and its point group is not known yet.展开更多
Ultrafine Y0.95–xGdxEu0.05Al3(BO3)4 phosphors with different Gd3+ concentrations were prepared by a solution combustion method, and characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM). Resu...Ultrafine Y0.95–xGdxEu0.05Al3(BO3)4 phosphors with different Gd3+ concentrations were prepared by a solution combustion method, and characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM). Results showed that the pure phase of YAl3(BO3)4 was obtained at 1000 oC and the prepared particle size varied with calcining temperatures. Photoluminescence spectra indicated that the dominant emission peak was observed at 612 nm due to the 5D0→7F2 transition of Eu3+. The luminescence intensity of ...展开更多
We evaluate and demonstrate ultra-broadband near-infrared noncollinear optical parametric amplification in two nonlinear crystals,bismuth borate(Bi BO)and yttrium calcium oxyborate(YCOB),which are not commonly used fo...We evaluate and demonstrate ultra-broadband near-infrared noncollinear optical parametric amplification in two nonlinear crystals,bismuth borate(Bi BO)and yttrium calcium oxyborate(YCOB),which are not commonly used for this application.The spectral bandwidth is of the microjoule level;the amplified signal is≥200 nm,capable of supporting sub-10 fs pulses.These results,supported by numerical simulations,show that these crystals have a great potential as nonlinear media in both low-energy,few-cycle systems and high peak power amplifiers for terawatt to petawatt systems based on noncollinear optical parametric chirped pulse amplification(NOPCPA)or a hybrid.展开更多
The effects of the addition of H3BO3 on the microstructure, phase formation, and microwave dielectric properties of （Zn0.TMg0.3）TiO3 ceramics sintered at temperatures ranging from 890 ℃ to 950 ℃ are investigated. ...The effects of the addition of H3BO3 on the microstructure, phase formation, and microwave dielectric properties of （Zn0.TMg0.3）TiO3 ceramics sintered at temperatures ranging from 890 ℃ to 950 ℃ are investigated. H3BO3 as a sintering agent can effectively lower the sintering temperature of ZMT ceramics below 950 ℃due to the liquid-phase effect. The microwave dielectric properties are found to strongly correlate with the amount of H3BO3. With the increase in H3BO3 content, the dielectric constant （er） monotonically increases, but the quality factor （Q x f） reaches a maximum at 1 wt% H3BO3, and the apparent density of ZMT ceramics with H3BO3〉 1 wt% gradually decreases. At 950 ℃, the ZMT ceramics with 1% H3BO3 exhibit excellent microwave dielectric properties： er = 19.8, and Q x f -- 43800 GHz （8.94 GHz）.展开更多
A series of red phosphors M3BO6:Eu3+(M=La,Y) were synthesized at 1150 oC by conventional solid state reaction method and their luminescent properties were investigated.Structural characterization of the luminescent ma...A series of red phosphors M3BO6:Eu3+(M=La,Y) were synthesized at 1150 oC by conventional solid state reaction method and their luminescent properties were investigated.Structural characterization of the luminescent materials was carried out with X-ray powder diffraction(XRD) analysis.Photoluminescence measurements indicated that the La3BO6:Eu3+ phosphor exhibited bright red emission centered at about 612 nm 626 nm under UV excited.La3BO6:Eu3+ phosphor had better luminescent intensity than Y3BO6:Eu3+ phosphors under the same excitation and measuring conditions.It was shown that the 0.08 mol.% Eu3+ ions in La3BO6:Eu3+ phosphors was optimal.The color parameter indicated that La3BO6:Eu3+ phosphor was a preferable red phosphor for white LED.展开更多
YbAl3(BO3)4 crystal of good optical quality was grown by the flux method. The structure of YbAl3(BO3)4 crystal was determined by single-crystal X-ray diffraction. The experiment shows that YbAl3(BO3)4 belongs to the d...YbAl3(BO3)4 crystal of good optical quality was grown by the flux method. The structure of YbAl3(BO3)4 crystal was determined by single-crystal X-ray diffraction. The experiment shows that YbAl3(BO3)4 belongs to the double bo-rates with a trigonal structure. The space group is R32 and its unit cell constants were measured to be a = 0.92965 nm, c=0.72129 nm, V = 0.53673 nm3, Z=3. The transmittance spectra were measured. The cut-off of YbAl3(BO3)4 crystal is 216 nm, and there are two absorption peaks located at 940 and 975 nm from 190 nm to 2600 nm. The thermal properties of YbAl3(BO3)4 crystal were studied for the first time. The average thermal expansion coefficients were determined to be 2×10-6/℃, 9.5×10-6/℃along a- and c- direction. The specific heat of YbAl3(BO3)4 crystal was measured to be 0.6695 J·(g·℃) -1 at room temperature . All results indicate that the YbAl3(BO3)4 crystal is an excellent stoichioimet-ric laser material.展开更多
A yellow phosphor, Ca2BO3CI：Eu2＋, is prepared by the high-temperature solid-state method. Under the condition of excitation sources ranging from ultraviolet to visible light, efficient yellow emission can be observe...A yellow phosphor, Ca2BO3CI：Eu2＋, is prepared by the high-temperature solid-state method. Under the condition of excitation sources ranging from ultraviolet to visible light, efficient yellow emission can be observed. The emission spectrum shows an asymmetrical single intensive band centred at 573 nm, which corresponds to the 4f65dl→4f7 transition of Eu2＋. Eu2＋ ions occupy two types of Ca2＋ sites in the Ca2BO3C1 lattice and form two corresponding emission centres, respectively, which lead to the asymmetrical emission of Eu2＋ in Ca2BO3C1. The emission intensity of Eu2＋ in Ca2BO3C1 is influenced by the Eu2＋ doping concentration. Concentration quenching is discovered, and its mechanism is verified to be a dipole-dipole interaction. The value of the critical transfer distance is calculated to be 2.166 nm, which is in good agreement with the 2.120 nm value derived from the experimental data.展开更多
文摘In the original publication,incorrect version of Corresponding authors has been published.You-Yuan Huang and Bo Wang should be corresponding authors.The corrected Correspondingg authors are provided in this correction.
文摘This article discussed the mechanisms and precautions of abdominal acupuncture from three different perspectives. First, the relationship between Shénquè （神阙 CV 8） and zang-fu and eight extra meridians stated in the ancient literature explained that the theory of CV 8 as the theoretical core of abdominal acupuncture therapy had literature support and theoretical evidence; second, with emphasis on the diagnosis and treatment based on differentiation of syndromes, four methods for selecting the points, including the ones according to hologram, meridians and collaterals, the Ba-kuo （八 廓） and three energizer, meanwhile, the origin of method selecting the points according to Three Energizer and clinical experience was also addressed; third, some problems about the manipulation of abdominal acupuncture therapy were put forward, such as selection of depth, direction, needle tool, as well as personal ideas and precautions, in order to ensure the clinical effect.
文摘Distinction between Crohn's disease of the colonrectum and ulcerative colitis or inflammatory bowel disease(IBD) type unclassified can be of pivotal importance for a tailored clinical management,as each entity often involves specific therapeutic strategies and prognosis.Nonetheless,no gold standard is available and the uncertainty of diagnosis may frequently lead to misclassification or repeated examinations.Hence,we have performed a literature search to address the problem of differential diagnosis in IBD colitis,revised current and emerging diagnostic tools and refined disease classification strategies.Nowadays,the differential diagnosis is an untangled issue,and the proper diagnosis cannot be reached in up to 10% of patients presenting with IBD colitis.This topic is receiving emerging attention,as medical therapies,surgical approaches and leading prognostic outcomes require more and more disease-specific strategies in IBD patients.The optimization of standard diagnostic approaches based on clinical features,biomarkers,radiology,endoscopy and histopathology appears to provide only marginal benefits.Conversely,emerging diagnostic techniques in the field of gastrointestinal endoscopy,molecular pathology,genetics,epigenetics,metabolomics and proteomics have already shown promising results.Novel advanced endoscopic imaging techniques and biomarkers can shed new light for the differential diagnosis of IBD,better reflecting diverse disease behaviors based on specific pathogenic pathways.
基金Guangdong Provincial Science&Technology Department and the Guangdong Provincial Academy of Chinese Medical Sciences(Development of Evidence-based Knowledge Management System for Traditional Chinese Medicine,No.2012A032500009)
文摘OBJECTIVE: To evaluate the reporting quality of randomized controlled trials(RCT) that compared Bo's abdominal acupuncture with conventional body acupuncture, and compare the efficacy and safetybetweenthembyperforminga Meta-analysis.METHODS: All RCTs comparing Bo's abdominalacupuncture with conventional body acupuncture were included. English and Chinese databases were searched from their respective inceptions to March 2014. The reporting quality was assessed according to the "Consolidated Standards of Reporting Trials"(CONSORT) checklist for parallel RCTs and the revised "Standards for Reporting Interventions in Clinical Trials of Acupuncture"(STRICTA). A Meta-analysis was conducted to synthesize the effect sizes,and publication bias was evaluated by the Egger linear regression test using Stata.RESULTS: Ninety-seven studies were included, of which most lacked adequate reporting information, and 80.4% showed that the efficacy of abdominal acupuncture is superior to conventional body acupuncture, especially for the following diseases:lumbar disc herniation, cervical spondylosis, omarthritis and cervical vertigo, except simple obesity.Effect-sizes were controversial when evaluating different outcomes.CONCLUSION: The international standard CONSORT statement and STRICTA guidelines should be strictly applied when reporting acupuncture RCTs in the future. Abdominal acupuncture appears to be more effective compared with conventional body acupuncture for some diseases. However, further high quality blind RCTs using validated outcomeindexesandstandardreportingarewarranted.
基金the National Natural Science Foundation of China (81560731),to Explore the Mechanism of the Regulation of Bo’s Abdominal Acupuncture on Obesity Type 2 Diabetes based on fibroblast growth factor 21 Signaling Pathway
文摘OBJECTIVE:To investigate the effect of Bo′s abdominal acupuncture(BOAA)on fibroblast growth factor 21(FGF21)and its related adipokines in type 2 diabetes mellitus(T2DM)rats.METHODS:This study established obese T2DM rat model by high-fat diet(HFD)with a dose of streptozotocin(STZ,30 mg/kg).Obese T2DM rats were randomly subdivided into four groups(n=10):negative,BOAA,conventional acupuncture(COA group)and metformin group(Met group)groups.The biochemical parameters,mRNAs,and proteins were analyzed using enzyme-lined immunoassays kits,quantitative polymerase chain reaction and Western blot.RESULTS:Treatment with BOAA attenuated the histopathological changes in visceral fat and restored the alterations in the levels of body weight,fasting blood glucose(FBG),homeostasis model assessment for insulin resistance(HOMA-IR).BOAA treatment significantly decreased the levels of triglyceride,total cholesterol,low density lipoprotein cholesterol,leptin,and increased the serum levels of high-density lipoprotein cholesterol,fibroblast growth factor 21(FGF21),adiponectin(ADP),peroxisome proliferator-activated receptorγ(PPAR-γ),C-peptide(C-P)in obese T2DM rats.Furthermore,BOAA treatment significantly increased the mRNA expressions of FGF21,ADP,leptin,PPAR-γ,PPAR-αand adenosine 5‘-monophosphate(AMP)-activated protein kinase(AMPK).Besides,BOAA treatment upregulated the protein expressions of fibroblast growth factor receptors3(FGFR3),PPAR-α,extracellular signal-regulated kinase(ERK),phosphorylated ERK(p-ERK),AMPK,p-AMPK,Liver kinase B1(LKB1),phosphorylated LKB1(p-LKB1),acetyl-CoA carboxylase(ACC)and phosphorylated ACC(p-ACC),while downregulated the protein expressions of FGF21 and PPAR-γin visceral fat.CONCLUSIONS:BOAA treatment reduced FBG and body weight,and improved insulin sensitivity through regulating FGF21 signaling pathway and its related adipokine in obese T2DM rats.
基金Project supported by National Natural Science Foundation of China (20871121)the Science Foundation for Young Scholar of Hanshan Normal University (LQ201001)the Scientific Research Fund for Doctoral Start-up Project of Hanshan Normal University
文摘The VUV-UV spectroscopic properties of Ce3＋ in Ba2Mg（BO3）2,Ba2Ca（BO3）2 and Sr2Mg（BO3）2 were compared,and the relation between the energy of the 4f→5d transition of Ce3＋ and the coordination environments of substituted alkaline earth ions was discussed.The chromaticity coordinates of Ce3＋ activated X2Z（BO3）2（X=Ba,Sr;Z=Ca,Mg） phosphors were changeable from blue to whitish and further to green range by varying the doping concentration of Ce3＋ or the types of substituted alkaline earth ions upon 172 nm excitation.
基金supported by the Major Research Project of Xi’an University of Arts and Science (No.zd200906)the Special Fund of Education Committee of Shaanxi Province (No.09JK743)
文摘The structure of LiSrY2（BO3）3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1（No.164）.The cell parameters at room temperature are as follows：a = 10.3345（9）,c = 6.4049（11） ,V = 592.41（13） 3,Z = 3,Mr = 448.81,F（000） = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B（2） atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2（BO3）3 and photoluminescence properties of the Eu3＋ doped LiSrY2（BO3）3 were also studied.
基金Project supported by the Ministry of Science and Technology of China (2006CB601104, 2008AA03A324)
文摘The (Y,Gd)BO3:Tb3+ and Li+-doped (Y,Gd)BO3:Tb3+ phosphors were prepared by high temperature solid-state method. The inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning electron microscopy (SEM), and the excitation and emission spectra were used to characterize the samples. The results of ICP-AES and XRD indicated that Li+ ions could enter the (Y,Gd)BO3:Tb3+ lattice and induce the lattice expansion. It could be seen from SEM that the particles were spherical a...
基金The work was supported by the National Natural Science Foundation of China (grant No. 69890235 and 59823003).
文摘The {0001} face develops on the habit of self-frequency doubling laser crystal Yb: YAI3(B03)4 (YbYAB) only under high growth rate condition, and its morphology is rough. To study the growth mechanism of {0001} face, we have observed the growth morphology on {0001} polishing section by atomic force microscopy (AFM). A series of AFM images captured in different growth durations on the {0001} polishing section reflect the crystal growth process. It is shown that the growth morphology on the {0001} polishing section was rough with many hillocks at the first growth stage, and it can become smooth finally, although the growth morphology on the {0001} face developed naturally on YbYAB crystal habit is always rough. On the smooth {0001} surface formed at the last growth stage, there are some triangular pits. This fact is different from that of hillocks in most crystal growth morphologies. AFM can easily distinguish the pits or hillocks on the surface, but differential interfere contrast microscopy (DIC) can not do. The orientation of the triangular pits is just the opposite to the triangular {0001} faces. The chemical etching pattern is also composed of this kind of triangular pits. These growth morphology and etching pattern of the {0001} faces show 3m symmetry, but the point group of YbYAB crystal is 32. The symmetric contradiction between morphology and point group does not exist for quartz, although which has the same point group as YbYAB. From quartz {0001} surface morphology we can distinguish the right form or left form of the crystal, but from YbYAB {0001} surface morphology we can not do. The reason for the symmetric contradiction between YbYAB {0001} surface morphology and its point group is not known yet.
基金Project supported by the Fundamental Research Funds for the Central Universities and Natural Science Basic Research Plan in Shaanxi Province of China (2009JQ6009)
文摘Ultrafine Y0.95–xGdxEu0.05Al3(BO3)4 phosphors with different Gd3+ concentrations were prepared by a solution combustion method, and characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM). Results showed that the pure phase of YAl3(BO3)4 was obtained at 1000 oC and the prepared particle size varied with calcining temperatures. Photoluminescence spectra indicated that the dominant emission peak was observed at 612 nm due to the 5D0→7F2 transition of Eu3+. The luminescence intensity of ...
基金the European Union’s Horizon 2020 research and innovation program under grant agreement No.871124(Laserlab-Europe)the Euratom research and training program 2014–2018 under grant agreement No.633053+1 种基金the Fundacao para a Ciencia e a Tecnologia(FCT,Lisboa)under grants Nos.PD/BD/114327/2016,PD/BD/135177/2017,PD/BD/135222/2017 and PINFRA/22124/2016the framework of the Advanced Program in Plasma Science and Engineering(APPLAu SE,sponsored by FCT under grant No.PD/00505/2012)at Instituto Superior Técnico(IST)。
文摘We evaluate and demonstrate ultra-broadband near-infrared noncollinear optical parametric amplification in two nonlinear crystals,bismuth borate(Bi BO)and yttrium calcium oxyborate(YCOB),which are not commonly used for this application.The spectral bandwidth is of the microjoule level;the amplified signal is≥200 nm,capable of supporting sub-10 fs pulses.These results,supported by numerical simulations,show that these crystals have a great potential as nonlinear media in both low-energy,few-cycle systems and high peak power amplifiers for terawatt to petawatt systems based on noncollinear optical parametric chirped pulse amplification(NOPCPA)or a hybrid.
基金supported by the National Natural Science Foundation of China(Grant Nos.61171047,51132003,51072029,and 61271038)the Program for New Century Excellent Talents in Universitythe Fund from the Science and Technology Department of Sichuan Province,China
文摘The effects of the addition of H3BO3 on the microstructure, phase formation, and microwave dielectric properties of （Zn0.TMg0.3）TiO3 ceramics sintered at temperatures ranging from 890 ℃ to 950 ℃ are investigated. H3BO3 as a sintering agent can effectively lower the sintering temperature of ZMT ceramics below 950 ℃due to the liquid-phase effect. The microwave dielectric properties are found to strongly correlate with the amount of H3BO3. With the increase in H3BO3 content, the dielectric constant （er） monotonically increases, but the quality factor （Q x f） reaches a maximum at 1 wt% H3BO3, and the apparent density of ZMT ceramics with H3BO3〉 1 wt% gradually decreases. At 950 ℃, the ZMT ceramics with 1% H3BO3 exhibit excellent microwave dielectric properties： er = 19.8, and Q x f -- 43800 GHz （8.94 GHz）.
基金Project supported by the Research Fund for Photoelectronic Material Base of Natural Science Foundation of Hebei Province (08B007)Natural Science Foundation of Hebei Province (A2010000184)
文摘A series of red phosphors M3BO6:Eu3+(M=La,Y) were synthesized at 1150 oC by conventional solid state reaction method and their luminescent properties were investigated.Structural characterization of the luminescent materials was carried out with X-ray powder diffraction(XRD) analysis.Photoluminescence measurements indicated that the La3BO6:Eu3+ phosphor exhibited bright red emission centered at about 612 nm 626 nm under UV excited.La3BO6:Eu3+ phosphor had better luminescent intensity than Y3BO6:Eu3+ phosphors under the same excitation and measuring conditions.It was shown that the 0.08 mol.% Eu3+ ions in La3BO6:Eu3+ phosphors was optimal.The color parameter indicated that La3BO6:Eu3+ phosphor was a preferable red phosphor for white LED.
基金Project supported by the National Natural Science Foundation of China (50323006 and 50590401/E01)
文摘YbAl3(BO3)4 crystal of good optical quality was grown by the flux method. The structure of YbAl3(BO3)4 crystal was determined by single-crystal X-ray diffraction. The experiment shows that YbAl3(BO3)4 belongs to the double bo-rates with a trigonal structure. The space group is R32 and its unit cell constants were measured to be a = 0.92965 nm, c=0.72129 nm, V = 0.53673 nm3, Z=3. The transmittance spectra were measured. The cut-off of YbAl3(BO3)4 crystal is 216 nm, and there are two absorption peaks located at 940 and 975 nm from 190 nm to 2600 nm. The thermal properties of YbAl3(BO3)4 crystal were studied for the first time. The average thermal expansion coefficients were determined to be 2×10-6/℃, 9.5×10-6/℃along a- and c- direction. The specific heat of YbAl3(BO3)4 crystal was measured to be 0.6695 J·(g·℃) -1 at room temperature . All results indicate that the YbAl3(BO3)4 crystal is an excellent stoichioimet-ric laser material.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10974013, 60978060, and 10804006)the Research Fund for the Doctoral Program of Higher Education, China (Grant No. 20090009110027)+5 种基金the Beijing Municipal Natural Science Foundation, China (Grant No. 1102028)the National Basic Research Program of China (Grant No. 2010CB327704)the National Natural Science Foundation for Distinguished Young Scholars (Grant No. 60825407)the Beijing Municipal Science and Technology Commission, China (Grant No. Z090803044009001)the Science Fund of the Key Laboratory of Luminescence and Optical Information, Beijing Jiaotong University, Ministry of Education, China (Grant No. 2010LOI12)the Excellent Doctor's Science and Technology Innovation Foundation of Beijing Jiaotong University, China (Grant No. 2011YJS073)
文摘A yellow phosphor, Ca2BO3CI：Eu2＋, is prepared by the high-temperature solid-state method. Under the condition of excitation sources ranging from ultraviolet to visible light, efficient yellow emission can be observed. The emission spectrum shows an asymmetrical single intensive band centred at 573 nm, which corresponds to the 4f65dl→4f7 transition of Eu2＋. Eu2＋ ions occupy two types of Ca2＋ sites in the Ca2BO3C1 lattice and form two corresponding emission centres, respectively, which lead to the asymmetrical emission of Eu2＋ in Ca2BO3C1. The emission intensity of Eu2＋ in Ca2BO3C1 is influenced by the Eu2＋ doping concentration. Concentration quenching is discovered, and its mechanism is verified to be a dipole-dipole interaction. The value of the critical transfer distance is calculated to be 2.166 nm, which is in good agreement with the 2.120 nm value derived from the experimental data.
