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Impact of mica on geotechnical behavior of weathered granitic soil using macro and micro investigations
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作者 Xianwei Zhang Xinyu Liu +3 位作者 Haodong Gao Gang Wang ran an Zhu Liang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2250-2266,共17页
The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This ... The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This study prepares reconstituted WGS with different mica contents by removing natural mica in theWGS,and then mixes it with commercial mica powders.The geotechnical behavior as well as the microstructures of the mixtures are characterized.The addition of mica enables the physical indices of WGS to be specific combinations of coarser gradation and high permeability but high Atterberg limits.However,high mica content in WGS was found to be associated with undesirable mechanical properties,including increased compressibility,disintegration,and swelling potential,as well as poor compactability and low effective frictional angle.Microstructural analysis indicates that the influence of mica on the responses of mixtures originates from the intrinsic nature of mica as well as the particle packing being formed withinWGS.Mica exists in the mixture as stacks of plates that form a spongy structure with high compressibility and swelling potential.Pores among the plates give the soil high water retention and high Atterberg limits.Large pores are also generated by soil particles with bridging packing,which enhances the permeability and water-soil interactions upon immersion.This study provides a microlevel understanding of how mica dominates the behavior of WGS and provides new insights into the effective stabilization and improvement of micaceous soils. 展开更多
关键词 Weathered granitic soil(WGS) MICA Microstructure Physical properties Mechanical properties Mechanism
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Site observations of weathered granitic soils subjected to cementation and partial drainage using SCPTU
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作者 Xianwei Zhang Xinyu Liu +1 位作者 ran an Xinming Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期984-996,共13页
Because of the cementation inherited from the parent rock,weathered granitic soil is usually susceptible to disturbance,which poses considerable challenges for laboratory characterization.The cone penetration test wit... Because of the cementation inherited from the parent rock,weathered granitic soil is usually susceptible to disturbance,which poses considerable challenges for laboratory characterization.The cone penetration test with pore pressure measurements has long been known for its reliability in site investigations and stratigraphic profiling.However,although extensive piezocone test results and experience are available for sedimentary soil,similar advances are yet to be made for weathered granitic soil.Moreover,the experience from sedimentary soil may not be directly applicable to weathered profiles because of the essentially different natures of the two types of geomaterials.This study performs seismic piezocone tests in a weathered granitic profile comprising residual granitic soil,completely weathered granite,and highly weathered granite.Pore pressure is measured at both the cone mid-face and the shoulder,and the effects of penetrometer size and penetration rate are considered.A series of updated soil behavior type charts is proposed to interpret the test results,thereby allowing the effect of weathering to be evaluated.This paper offers an important extension to the sparse data on the in situ responses of weathered materials. 展开更多
关键词 Weathered granite Seismic piezocone test CEMENTATION Soil classification Pore pressure Weathering degree
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Behavior of exciton in direct−indirect band gap Al_(x)Ga_(1−x)As crystal lattice quantum wells
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作者 Yong Sun Wei Zhang +10 位作者 Shuang Han ran an Xin-Sheng Tang Xin-Lei Yu Xiu-Juan Miao Xin-Jun Ma Xianglian Pei-Fang Li Cui-Lan Zhao Zhao-Hua Ding Jing-Lin Xiao 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期64-70,共7页
Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is a... Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is also found to influence the study of exciton ground state energy and ground state binding energy in Al_(x)Ga_(1−x)As semiconductor spherical quantum dots.The Al_(x)Ga_(1−x)As is considered to be a direct semiconductor at AI concentration below 0.45,and an indirect one at the concentration above 0.45.With regards to the former,the ground state binding energy increases and decreases with AI concentration and eigenfrequency,respectively;however,while the ground state energy increases with AI concentration,it is marginally influenced by eigenfrequency.On the other hand,considering the latter,while the ground state binding energy increases with AI concentration,it decreases with eigenfrequency;nevertheless,the ground state energy increases both with AI concentration and eigenfrequency.Hence,for the better practical performance of the semiconductors,the properties of the excitons are suggested to vary by adjusting AI concentration and eigenfrequency. 展开更多
关键词 exciton effects aluminum gallium arsenide crystal direct band gap semiconductor indirect band gap semiconductor
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Chemoradiotherapy plus tislelizumab for mismatch repair proficient rectal cancer with supraclavicular lymph node metastasis:A case report
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作者 Wen-Tao Zhong Yuan Lv +3 位作者 Qian-Yu Wang ran an Gang Chen Jun-Feng Du 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2219-2224,共6页
BACKGROUND According to the latest report,colorectal cancer is still one of the most prevalent cancers,with the third highest incidence and mortality worldwide.Treatment of advanced rectal cancer with distant metastas... BACKGROUND According to the latest report,colorectal cancer is still one of the most prevalent cancers,with the third highest incidence and mortality worldwide.Treatment of advanced rectal cancer with distant metastases is usually unsatisfactory,especially for mismatch repair proficient(pMMR)rectal cancer,which leads to poor prognosis and recurrence.CASE SUMMARY We report a case of a pMMR rectal adenocarcinoma with metastases of multiple lymph nodes,including the left supraclavicular lymph node,before treatment in a 70-year-old man.He received full courses of chemoradiotherapy(CRT)followed by 4 cycles of programmed death 1 inhibitor Tislelizumab,and a pathologic complete response(pCR)was achieved,and the lesion of the left supraclavicular lymph node also disappeared.CONCLUSION pMMR advanced rectal cancer with preserved intact distant metastatic lymph nodes may benefit from full-course CRT combined with immunotherapy. 展开更多
关键词 Rectal cancer METASTASIS CHEMORADIOTHERAPY IMMUNOTHERAPY PROGNOSIS Case report
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Effects of dry-wet cycles on three-dimensional pore structure and permeability characteristics of granite residual soil using X-ray micro computed tomography 被引量:12
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作者 ran an Lingwei Kong +1 位作者 Xianwei Zhang Chengsheng Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第3期851-860,共10页
Due to seasonal climate alterations,the microstructure and permeability of granite residual soil are easily affected by multiple dry-wet cycles.The X-ray micro computed tomography(micro-CT)acted as a nondestructive to... Due to seasonal climate alterations,the microstructure and permeability of granite residual soil are easily affected by multiple dry-wet cycles.The X-ray micro computed tomography(micro-CT)acted as a nondestructive tool for characterizing the microstructure of soil samples exposed to a range of damage levels induced by dry-wet cycles.Subsequently,the variations of pore distribution and permeability due to drywet cycling effects were revealed based on three-dimensional(3D)pore distribution analysis and seepage simulations.According to the results,granite residual soils could be separated into four different components,namely,pores,clay,quartz,and hematite,from micro-CT images.The reconstructed 3D pore models dynamically demonstrated the expanding and connecting patterns of pore structures during drywet cycles.The values of porosity and connectivity are positively correlated with the number of dry-wet cycles,which were expressed by exponential and linear functions,respectively.The pore volume probability distribution curves of granite residual soil coincide with the χ^(2)distribution curve,which verifies the effectiveness of the assumption of χ^(2)distribution probability.The pore volume distribution curves suggest that the pores in soils were divided into four types based on their volumes,i.e.micropores,mesopores,macropores,and cracks.From a quantitative and visual perspective,considerable small pores are gradually transformed into cracks with a large volume and a high connectivity.Under the action of dry-wet cycles,the number of seepage flow streamlines which contribute to water permeation in seepage simulation increases distinctly,as well as the permeability and hydraulic conductivity.The calculated hydraulic conductivity is comparable with measured ones with an acceptable error margin in general,verifying the accuracy of seepage simulations based on micro-CT results. 展开更多
关键词 Granite residual soil Dry-wet cycle X-ray micro computed tomography(micro-CT) Three-dimensional(3D)pore distribution Seepage simulations PERMEABILITY
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Evolution of cracks in the shear bands of granite residual soil 被引量:4
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作者 Chengsheng Li Lingwei Kong ran an 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第6期1956-1966,共11页
The evolution of shear bands and cracks plays an important role in landslides.However,there is no systematic method for classification of the cracks,which can be used to analyze the evolution of cracks in shear bands.... The evolution of shear bands and cracks plays an important role in landslides.However,there is no systematic method for classification of the cracks,which can be used to analyze the evolution of cracks in shear bands.In this study,X-ray computed tomography(CT)is used to observe the behavior of granite residual soil during a triaxial shear process.Based on the digital volume correlation(DVC)method,a crack classification method is established according to the connectivity characteristics of cracks before and after loading.Cracks are then divided into six classes:obsolete,brand-new,isolated,split,combined,and compound.With evolution of the shear bands,a large number of brand-new cracks accelerate the damages of materials at the mesoscale,resulting in a sharp decrease in strength.The volume of brandnew cracks increases rapidly with increasing axial strain,and their volume is greater than 50%when the strain reaches 12%,while the volume of compound cracks decreases from 54%to 21%.As cracks are the weakest areas in a material,brand-new cracks accelerate the development of shear bands.Finally,the coupling effect of shear bands and cracks destroys the soil strength. 展开更多
关键词 Shear band Crack classification method Digital volume correlation(DVC) X-ray computed tomography(CT) Granite residual soil
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Penile vascular anomalies:A retrospective single center study and cumulative analysis of studies from China
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作者 Chong Ma Feng Gao +3 位作者 ran an Yawei Guan Jingfei Teng Xing Ai 《Asian Journal of Urology》 CSCD 2023年第4期555-562,共8页
Objective Penile vascular anomalies(PVAs)or hemangioma can arouse patient concern about aesthetics and cause symptoms like bleeding and sexual dysfunction.However,its low incidence and the deficiency of large-volume s... Objective Penile vascular anomalies(PVAs)or hemangioma can arouse patient concern about aesthetics and cause symptoms like bleeding and sexual dysfunction.However,its low incidence and the deficiency of large-volume studies hinder urologists from making informed decisions.This study aimed to investigate the clinical features and treatment experience of PVAs at the Seventh Medical Center of PLA General Hospital,Beijing,China.Furthermore,by systematically analysis of studies on PVAs in Chinese people,we aimed to provide novel insights on the management of this condition.Methods We retrospectively investigated clinical features and pathology of surgery-treated PVAs at our center.Moreover,by systemically reviewing the literature from PubMed and the three largest medical databases(China National Knowledge Infrastructure,Wan Fang,and Chinese Medical Journal Database)in China,we analyzed the clinical features and various therapies of PVAs in Chinese people.Results Between March 1,2018 and March 1,2023,a total of 356 cases with vascular anomalies were treated with surgery at out center.Only seven(2.0%)cases had lesions involving the perineum and external genitalia.All the seven cases were pathologically benign and demonstrated no recurrence over a follow-up period of 1-52 months(median 14 months).A total of 410 cases from 44 studies were selected in the cumulative analysis.Most patients(92.4%)diagnosed with PVAs were asymptomatic,and 68.8%of the patients were treated with sclerotherapy.As to the pathology,57.1%were venous malformation.Conclusion The most common PVA is venous malformation and the majority of patients are asymptomatic.Sclerotherapy and laser have emerged as viable options for treating small lesions.Surgery still has its role in treating large lesions and obtaining pathology.Although PVAs often relapse or demand multiple treatments,the prognosis is favorable. 展开更多
关键词 HEMANGIOMA Laser irradiation PENIS Surgery Vascular anomaly
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Global trends and knowledge-relationship of symptom clusters in cancer research:a bibliometric analysis over the past 20 years
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作者 ran an Yuan Luo +2 位作者 Wen-Feng Chen Muhammad Sohaib Mei-Zi Liu 《Frontiers of Nursing》 2023年第3期273-288,共16页
Objective:To use Cite Space and VOSviewer to investigate the scientific production in the field of symptom clusters in cancer research.Methods:The search was performed using the terms“symptom clusters,”“cancer,”an... Objective:To use Cite Space and VOSviewer to investigate the scientific production in the field of symptom clusters in cancer research.Methods:The search was performed using the terms“symptom clusters,”“cancer,”and“oncology”on the Web of Science Core Collection database.The retrieval time was from 2001 to 2021,which covers the last 2 decades.Based on the production theory of scientific knowledge and the data mining of citations,data pertaining to the annual publications,journals,countries,organizations,authors,and keywords that produce symptom clusters in cancer research,as well as their cooperation(collaboration network),were extracted,and then both were clarified by the software tools VOSviewer(version 1.6.16)and Cite Space(version 6.1.R2).Results:A total of 1796 publications were retrieved between 2001 and 2021,and 473 relevant publications were included after screening.The results showed an increasing trend in published articles.The United States had the largest number of publications(261/473,55.18%),followed by China and Canada.The University of California,San Francisco,was the most productive institution.Current research hotspots included the analysis of symptom clusters and symptom management in patients with breast cancer and lung cancer,as well as any advanced cancer and cancer cachexia;fatigue-related symptom clusters and depression-anxiety symptom cluster;and the impacts of symptom clusters on quality of life.The research frontiers included analysis between health-related quality of life and symptom clusters,data mining in symptom clusters,research on the mental health status of cancer patients,and study of the mechanism and biological pathways of symptom clusters.Conclusions:The study provides insight into the global research perspective for the scientific progress on cancer symptom clusters,which suggests a growing scientific interest in this field,and more studies are warranted to guide symptom management. 展开更多
关键词 BIBLIOMETRICS cancer Citespace symptom clusters systematic review VOSviewer
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Gastric adenosquamous carcinoma with an elevated serum level of alpha-fetoprotein:A case report
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作者 Liang Sun Juan-Juan Wei +6 位作者 ran an Hui-Yun Cai Yuan Lv Tao Li Xiao-Fei Shen Jun-Feng Du Gang Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2357-2361,共5页
BACKGROUND Gastric adenosquamous carcinoma(ASC)is rare and characterized by coexisting of adenocarcinoma andsquamous carcinoma within the same tumor.We present a female patient with gastric ASC who had an elevated ser... BACKGROUND Gastric adenosquamous carcinoma(ASC)is rare and characterized by coexisting of adenocarcinoma andsquamous carcinoma within the same tumor.We present a female patient with gastric ASC who had an elevated serum level of alpha-fetopro-tein(AFP),which decreased to normal levels after a laparoscopic distant radical gastrectomy in a short period.The clinicopathological features in AFP-producing gastric cancer(GC)are discussed,as well as potentially available prognostic predi-ctors.CASE SUMMARY A 50-year-old woman presented to our department with a chief complain of a 6-mo history of bloating.She had no basic diseases including heart diseases and respiratory diseases,and she also denied any prior history of dysphagia,hematemesis,melena,rectal bleeding,hematochezia,or unintentional weight loss.Based on her symptoms,an esophagogastroduodenoscopy was performed,showing an annular cavity lesion 3 cm from the pylorus with a diameter of 6 cm.A biopsy of the lesion showed gastric ASC,whereas the pylorus biopsy showed normal mucosa.The patient further received an enhanced computed tomography scan which demonstrated an invasive lesion close to the pylorus with a still clear margin of the tumor to peripheral organs such as the pancreas and liver.Scattered lymph nodes were visible around,whereas no sign of liver metastasis was discovered.Serum tumor markers including carcinoembryonic antigen(CEA),cancer antigen 199(CA199),CA724,CA125,and CA242 were all normal,while the level of serum AFP increased to 172 ng/mL.A laparoscopic distant radical gastrectomy was performed after exclusion of surgical contraindications.Postoperative pathology results showed that the tumor displayed an ulcerated ASC phenotype(90%of medium to highly-differentiated squamous cell carcinoma,10%of poorly differentiated adenocarcinoma.Surprisingly,the serum level of AFP decreased to normal level on post operation day 5.The tumor cells were positive for CK5/6,p63,and CEA,and negative for AFP and Epstein-Barr encoding region.CONCLUSION We presented a rare case of gastric ASC with elevated serum AFP level,which may be new subtype of AFP-producing GC.Follow-up detection of serum AFP might be a useful tool to predict patient prognosis. 展开更多
关键词 Gastric cancer Gastric adenosquamous carcinoma ALPHA-FETOPROTEIN Case report
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Review on birefringence in borates based on birefringence-active functional groups and arrangements
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作者 Qianzhen Zhang ran an +3 位作者 Zhihua Yang Xifa Long Shilie Pan Yun Yang 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第7期2155-2170,共16页
As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the n... As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the nonlinear optical crystals.The big birefringence not only benefits to the miniaturization of related devices,but also broadens the phase-matching wavelength range of nonlinear optical crystals.The design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology fields.Herein,crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups,and the relationship between structure and properties is thoroughly explored.It is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence. 展开更多
关键词 BIREFRINGENCE BORATE optical functional crystal structural anisotropy arrangement of functional units
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Cronkhite-Canada syndrome polyps infiltrated with IgG4-positive plasma cells 被引量:4
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作者 Ru-Ying Fan Xiao-Wei Wang +2 位作者 Li-Jun Xue ran an Jian-Qiu Sheng 《World Journal of Clinical Cases》 SCIE 2016年第8期248-252,共5页
Cronkhite-Canada syndrome(CCS) is a rare but serious protein-losing enteropathy, but little is known about the mechanism. Further more, misdiagnosis is common due to non-familiarity of its clinical manifestation. A 40... Cronkhite-Canada syndrome(CCS) is a rare but serious protein-losing enteropathy, but little is known about the mechanism. Further more, misdiagnosis is common due to non-familiarity of its clinical manifestation. A 40-year-old male patient was admitted to our hospital because of diarrhea and hypogeusia associated with weight loss for 4 mo. On physical examination, skin pigmentation, dystrophic nail changes and alopecia were noted. He had no alike family history. Laboratory results revealed low levels of serum albumin(30.1 g/L, range: 35.0-55.0 g/L), serum potassium(2.61 mmol/L, range: 3.5-5.5 mmol/L) and blood glucose(2.6 mmol/L, range: 3.9-6.1 mmol/L). The erythrocyte sedimentation rate was elevated to 17 mm/h(range: 0-15 mm/h). X-ray of chest and mandible was normal. The endoscopic examination showed multiple sessile polyps in the stomach, small bowel and colorectum. Histopathologic examination of biopsies obtained from those polyps showed hyperplastic change, cystic dilatation and distortion of glands with inflammatory infiltration, eosinophilic predominance and stromal edema. Immune staining for IgG 4 plasma cells was positive in polyps of stomach and colon. The patient was diagnosed of CCS and treated with steroid, he had a good response to steroid. Both histologic findings and treatment response to steroid suggested an autoimmune mechanism underling CCS. 展开更多
关键词 Gastrointestinal POLYPOSIS Cronkhite-Canada SYNDROME IGG4 plasma cells Autoimmune mechanism
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Simulation and design of a heat-integrated double-effect reactive distillation process for propylene glycol methyl ether production
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作者 ran an Shengxin Chen +5 位作者 Shun Hou Yuting Zhu Chunhu Li Xinbao Zhu Ruixia Liu Weizhong an 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第12期103-114,共12页
A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy cons... A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy consumption in the tubular plug-flow reactor.A single-column reactive distillation(RD)process was conducted under optimized operating conditions based on sensitivity analysis as a reference.The results demonstrated that the proposed DERD process is able to achieve more than 95%selectivity of the desired product.After that,a design approach of the DERD process with an objective of the minimum operating cost was proposed to achieve further energy savings in the RD process.The proposed DERD configuration can provide a large energy-savings by totally utilization of the overhead vapor steam in the high-pressure RD column.A comparison of the single-column RD process revealed that the proposed DERD process can reduce the operating cost and the total annual cost of 25.3%and 30.7%,respectively,even though the total capital cost of DERD process is larger than that of the RD process. 展开更多
关键词 Propylene oxide Reactive distillation Heat integration Propylene glycol monomethyl ether Process simulation
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Diagnosis of knee osteoarthritis by OCT and surface-enhanced Raman spectroscopy
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作者 ran an Huaimin Gu +6 位作者 Zhouyi Guo Huiqing Zhong Huajiang Wei Guoyong Wu Yonghong He Shusen Xie Hongqin Yang 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第5期13-27,共15页
In this paper,optical coherence tomography(OCT)and surface-enhanced Raman spectroscopy(SERS)were used to characterize normal knee joint(NKJ)tissue and knee osteoarthritis(KOA)tissue ex vivo.OCT images show that there ... In this paper,optical coherence tomography(OCT)and surface-enhanced Raman spectroscopy(SERS)were used to characterize normal knee joint(NKJ)tissue and knee osteoarthritis(KOA)tissue ex vivo.OCT images show that there is a clear hierarchical structure in NKJ tissue,including surface layer,transitional layer,radiation layer and cartilage matrix calcification layer tissue structure,while the hierarchical structure of KOA tissue is not clear and unevenly distributed,and the pathological tissues at different stages also show significant di®erences.SERS shows that NKJ tissue and mild osteoarthritic knee cartilage(MiKOA)tissue have strong characteristic Raman peaks at 964,1073(1086),1271,1305,1442,1660 and 1763 cm^(-1).Compared with the Raman spectrum of NKJ tissue,the Raman characteristic peaks of MiKOA tissue have some shifts,moving from 1073 cm^(-1)to 1086 cm^(-1)and from 1542 cm^(-1)to 1442 cm^(-1).There is a characteristic Raman peak of 1271 cm^(-1)in MiKOA tissue,but not in NKJ tissue.Compared with NKJ tissue,severely degenerated cartilage(SdKOA)tissues show some new SERS peaks at 1008,1245,1285,1311 and 1321 cm^(-1),which are not seen in SERS spectra of NKJ tissue.Principal component analysis(PCA)was used to analyze the Raman spectra of 1245–1345 cm^(-1)region.The results show that PCA can distinguish NKJ,MiKOA and SdKOA tissues and the accuracy is about 90%.These results indicate that OCT can clearly distinguish NKJ,MiKOA,moderate osteoarthritic knee cartilage(MoKOA)and SdKOA tissue,while SERS can provide further judgment basis.The results also prove that the contents of protein and polysaccharide in knee tissue are changed during the pathological process of knee tissue,which is the cause of pain caused by poor friction in knee joint during movement. 展开更多
关键词 Optical coherence tomography surface-enhanced Raman spectroscopy knee osteoarthritis.
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International Comparison,Regional Characteristics and Regulatory Management of Structural Rise in the Prices of Chinese Industrial and Agricultural Products
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作者 Ming ZHanG Hong Tan +1 位作者 ran an Zhibo ZHOU 《Asian Agricultural Research》 2014年第4期1-4,9,共5页
China's price fluctuations increasingly exhibit significant structural characteristics,and since 2003,there have been several rounds of significant structural price rise.The degree of structural rise in the prices... China's price fluctuations increasingly exhibit significant structural characteristics,and since 2003,there have been several rounds of significant structural price rise.The degree of structural rise in the prices of industrial and agricultural products in China is not only higher than in the general developed countries and developing countries,but also more prominent than in other transition economies.And the structural rise in the prices of Chinese industrial and agricultural products exhibits significant economic zone differences:the structural fluctuations are the greatest in the central and western regions,significantly higher than in the eastern regions as well as the national average.From the perspective of causes of structural rise in the prices of Chinese industrial and agricultural products,the government must aim to coordinate the industrial and agricultural investments and bridge the gap in the industrial and agricultural technologies and supply capacity. 展开更多
关键词 The PRICES of INDUSTRIAL and agricultural products
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Comparison of Electronic Taxpayer Services in OECD Countries and Recommendations for China
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作者 Deyong WU ran an Zhibo ZHOU 《Asian Agricultural Research》 2013年第12期12-15,20,共5页
Through comparing development trend electronic taxpayer services in OECD countries and analyzing its drawbacks,it gained beneficial experience of electronic taxpayer services.Then,it came up with policy recommendation... Through comparing development trend electronic taxpayer services in OECD countries and analyzing its drawbacks,it gained beneficial experience of electronic taxpayer services.Then,it came up with policy recommendations for China.It is recommended that China should raise the electronic taxpayer services to national strategy level,improve the efficiency of electronic taxpayer services in line with the taxpayercentered principle,develop ways of electronic taxpayer services with Chinese characteristics,increase convenience for taxpayers on the precondition of guaranteeing information security,make effort to reduce compliance costs of taxpayers,and promote popularization of electronic taxpayer services with the framework of laws. 展开更多
关键词 TAXPAYER SERVICES E-GOVERNMENT WHOLE of GOVERNMENT
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某型磁悬浮鼓风机在高压力非喘振区的失稳分析及解决方案
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作者 李瑜 王本义 +2 位作者 安然 乔巍 季玲 《风机技术》 2023年第S01期78-81,共4页
某新研发的磁悬浮鼓风机在高压力非喘振区运行时出现噪声大、转子失稳、转速无法提高等问题。根据主动控制磁轴承所监测的转子径向、轴向位移以及轴向推力等数据,结合CFD仿真分析,查出从扩压器流出的气流因受到非正常凸出的蜗舌干扰,在... 某新研发的磁悬浮鼓风机在高压力非喘振区运行时出现噪声大、转子失稳、转速无法提高等问题。根据主动控制磁轴承所监测的转子径向、轴向位移以及轴向推力等数据,结合CFD仿真分析,查出从扩压器流出的气流因受到非正常凸出的蜗舌干扰,在蜗壳出口区域产生回流,导致鼓风机转子受到异常的轴向冲击力。由于转子质量小,加速度响应快,轴向磁轴承难以及时控制,最终引发转子失稳。通过去除凸出蜗舌,消除了蜗壳内回流,该问题得到了解决。 展开更多
关键词 磁悬浮鼓风机 主动控制磁轴承 蜗舌 失稳 数值仿真 轴向推力
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Hydrochemical Characterization,Controlling Factors and Water Quality of Surface Water in Shandong Province,North China
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作者 ran an Jiutan Liu +2 位作者 Zongjun Gao Changsuo Li Yuming Peng 《Journal of Earth Science》 SCIE CAS CSCD 2024年第1期155-166,共12页
In this study,90 surface water samples were collected from Shandong Province(SDP)in the dry and wet seasons and analyzed using statistical analysis,hydrochemical methods and water quality index(WQI).The content of mai... In this study,90 surface water samples were collected from Shandong Province(SDP)in the dry and wet seasons and analyzed using statistical analysis,hydrochemical methods and water quality index(WQI).The content of main ions showed seasonal variations,with a higher average value in the dry season than in the wet season.Sampling points exhibiting high contents of the main chemical components were mainly distributed in areas southwest of SDP,north of Weifang,and around Jinan.The saturation index of carbonate minerals was greater than zero,while that of evaporite minerals was less than zero.The hydrochemical characteristics of surface water are mainly dominated by rock weathering as well as cation exchange.In addition,surface water in SDP has significantly been affected by anthropogenic factors.Most of the surface water could be classified as weakly alkaline soft-fresh water,with the hydrochemical types of SO_(4)·Cl-Ca·Mg and SO_(4)·Cl-Na.In terms of WQI,47.88% and 37.88% of the water samples in SDP were classified as poor water in the dry and wet seasons,respectively.On the whole,the water quality is higher in the wet season than in the dry season,and surface water in SDP is generally suitable for agricultural irrigation. 展开更多
关键词 surface water hydrochemical characteristics controlling factors water quality Shandong Province
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Groundwater Quality and Vulnerability Assessment in a Semiarid Karst Region of Northern China
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作者 ran an Shu Wang +5 位作者 Zongjun Gao Zhenyan Wang Wei Li Qijun Deng Lü Lin Yuanqing Liu 《Journal of Earth Science》 SCIE CAS CSCD 2024年第1期313-316,共4页
Groundwater plays a critical role in maintaining ecological balance and ensuring social operations,especially in arid and semiarid regions(Hu et al.,2023;Han et al.,2022;Ma et al.,2014).The over-exploitation of ground... Groundwater plays a critical role in maintaining ecological balance and ensuring social operations,especially in arid and semiarid regions(Hu et al.,2023;Han et al.,2022;Ma et al.,2014).The over-exploitation of groundwater,coupled with the influx of pollutants from human activities into the soil,significantly degrades the environment in certain regions(Jia et al.,2019;Famiglietti,2014;Giordano,2009;Konikow and Kendy,2005;Bohlke,2002;Shah et al.,2000). 展开更多
关键词 GROUNDWATER GROUNDWATER Vul
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基于信息生态观的高校图书馆数据资源优化配置研究
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作者 储继华 陈燕方 +1 位作者 安然 苗林 《科技创业月刊》 2022年第2期92-97,共6页
从信息生态观视角研究分析数据资源优化配置对于促进图书馆文献资源系统平衡与健康发展的重要意义。图书馆数据资源具有信息多样性和存储动态的特征,是一个信息生态系统,资源进化和资源配置是这一信息生态系统自我调节、维持相对稳定的... 从信息生态观视角研究分析数据资源优化配置对于促进图书馆文献资源系统平衡与健康发展的重要意义。图书馆数据资源具有信息多样性和存储动态的特征,是一个信息生态系统,资源进化和资源配置是这一信息生态系统自我调节、维持相对稳定的重要因子。利用生态学的观点与理论,探索分析图书馆数据资源组织构建、优化配置的思路与重点,解决数据资源生态失调现象,让有限的数据资源发挥出最大效能,更加便捷高效获取信息,发挥高校图书馆在“双一流”学科建设中文献资源支撑保障作用。 展开更多
关键词 信息生态 数据资源 资源评估 资源配置
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Efficient one-pot synthesis of n-butyl levulinate from carbohydrates catalyzed by Fe_2(SO_4)_3 被引量:8
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作者 ran an Guizhuan Xu +2 位作者 Chun Chang Jing Bai Shuqi Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期556-563,共8页
Butyl levulinate(BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the cat... Butyl levulinate(BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the catalysis of metal sulfates was developed. The catalytic activity of a series of metal sulfates for the synthesis of BL from fructose was investigated. Among various metal sulfates, ferric sulfate Fe(SO)was found to be the most efficient catalyst, which gave a remarkably high BL yield of 62.8 mol% under the conditions of 463 K, 3 h, a catalyst dosage of 5.0 g/L, and fructose concentration of 25 g/L. Different carbohydrates including glucose, cellulose, inulin and sucrose were also used for one-pot synthesis of BL with the catalysis of Fe(SO), showing the yields of 39.6, 30.5, 56.6 and 50.1 mol%, respectively. In addition,the recycling and reuse of Fe(SO)was studied by characterizing them using powder X-ray diffraction(XRD), scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS). A plausible reaction pathway for the one-pot synthesis of BL from fructose was proposed. This study provides a facile and feasible way for the synthesis of BL from biomass. 展开更多
关键词 ONE-POT n-butyl levulinate Metal sulfate Carbohydrates
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