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TA15/TaZrNb multi-element alloy prepared via diffusion bonding:Tensile-strength model and performance of a representative volume element embedded with a sphere
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作者 Wei Chen Fenglei Huang +4 位作者 Chuanting Wang Ruijun Fan Pengjie Zhang Lida Che Aiguo Pi 《Defence Technology(防务技术)》 2025年第8期36-51,共16页
In this study, to meet the development and application requirements for high-strength and hightoughness energetic structural materials, a representative volume element of a TA15 matrix embedded with a TaZrNb sphere wa... In this study, to meet the development and application requirements for high-strength and hightoughness energetic structural materials, a representative volume element of a TA15 matrix embedded with a TaZrNb sphere was designed and fabricated via diffusion bonding. The mechanisms of the microstructural evolution of the TaZrNb/TA15 interface were investigated via SEM, EBSD, EDS, and XRD.Interface mechanical property tests and in-situ tensile tests were conducted on the sphere-containing structure, and an equivalent tensile-strength model was established for the structure. The results revealed that the TA15 titanium alloy and joint had high density and no pores or cracks. The thickness of the planar joint was approximately 50-60 μm. The average tensile and shear strengths were 767 MPa and 608 MPa, respectively. The thickness of the spherical joint was approximately 60 μm. The Zr and Nb elements in the joint diffused uniformly and formed strong bonds with Ti without forming intermetallic compounds. The interface exhibited submicron grain refinement and a concave-convex interlocking structure. The tensile fracture surface primarily exhibited intergranular fracture combined with some transgranular fracture, which constituted a quasi-brittle fracture mode. The shear fracture surface exhibited brittle fracture with regular arrangements of furrows. Internal fracture occurred along the spherical interface, as revealed by advanced in-situ X-ray microcomputed tomography. The experimental results agreed well with the theoretical predictions, indicating that the high-strength interface contributes to the overall strength and toughness of the sphere-containing structure. 展开更多
关键词 Diffusion bonding multi-element alloy Joint microstructure In-situ mechanical test X-ray mCT Sphere-containing structure
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Enhanced recovery after surgery-based recovery room nursing improves perioperative safety in gastrointestinal tumor surgery
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作者 Wan-Qi Zhong Su Wu +6 位作者 Ru-Xin Jiang Shao-Ru Chen Dan-Yang Li Jun Zhou Jiang-Xia Wu Ruo-Jing Zeng Hui Zhi 《World Journal of Gastrointestinal Oncology》 2026年第1期211-220,共10页
BACKGROUND Gastrointestinal(GI)tumors are among the most prevalent malignancies,and surgical intervention remains a primary treatment modality.However,the complexity of GI surgery often leads to prolonged recovery and... BACKGROUND Gastrointestinal(GI)tumors are among the most prevalent malignancies,and surgical intervention remains a primary treatment modality.However,the complexity of GI surgery often leads to prolonged recovery and high postoperative complication rates,which threaten patient safety and functional outcomes.Enhanced recovery after surgery(ERAS)principles have been shown to improve perioperative outcomes through evidence-based,multidisciplinary care pathways.Despite its widespread adoption,there is a paucity of research focusing specifically on optimizing ERAS-guided nursing processes in the post-anesthesia care unit(PACU)and evaluating its impact on perioperative safety in patients undergoing GI tumor surgery.This study aimed to investigate whether an ERASbased PACU nursing protocol could enhance recovery,reduce complications,and improve patient safety in this surgical population.AIM To explore the impact of optimizing the recovery room nursing process based on ERAS on the perioperative safety of patients with GI tumors.METHODS A total of 260 patients with GI tumors who underwent elective surgeries under general anesthesia in our hospital from August 2023 to August 2025 and were then observed in the recovery unit(PACU)were selected.They were randomly divided into the observation group(the PACU nursing process was optimized based on ERAS)and the control group(the conventional PACU nursing process was adopted)by the random number grouping method,with 130 cases in each group.The time of gastric tube removal,urinary catheter removal,defecation time,hospital stay,time of leaving the room after tube removal,retention time in the recovery room,occurrence of complications,satisfaction and readmission rate were compared between the two groups after entering the room.Compare the occurrence of adverse events in the PACU nursing process between the two groups.RESULTS The time of gastric tube removal,urinary catheter removal,defecation time,hospital stay,retention time in the recovery room,total incidence of complications and readmission rate in the observation group were significantly lower than those in the control group,and the satisfaction rate was higher than that in the control group(P<0.05).The occurrence of adverse events in the PACU nursing process in the observation group was lower than that in the control group(P<0.05).CONCLUSION Optimizing the PACU nursing process based on ERAS can effectively accelerate the recovery process of patients undergoing GI tumor surgery,reduce adverse events,improve nursing satisfaction,and at the same time,lower the incidence of adverse events in the PACU nursing process,providing a more refined management basis for clinical practice. 展开更多
关键词 Enhanced recovery after surgery recovery room NURSING Gastrointestinal tumors Perioperative period
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Evidence-based acupuncture:Methodological insights and challenges in gastroenteroscopy recovery research
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作者 Jia-Le Zhang Liang-Zhen You 《World Journal of Gastroenterology》 2026年第2期10-17,共8页
This editorial examines the emerging potential of traditional Chinese medicine(TCM)in enhancing postoperative recovery following gastroenteroscopy,highlighted by a 2025 randomized controlled trial by Hong et al.The st... This editorial examines the emerging potential of traditional Chinese medicine(TCM)in enhancing postoperative recovery following gastroenteroscopy,highlighted by a 2025 randomized controlled trial by Hong et al.The study,involving 120 patients,demonstrates that meridian flow injection(MFI)combined with transcutaneous electrical acupoint stimulation(TEAS)significantly improves gastrointestinal(GI)function,evidenced by a reduced time to first defecation(3.20±1.04 days vs 3.98±1.27 days,P<0.001),lowers stress biomarkers(e.g.,reduced cortisol and norepinephrine),and enhances clinical efficacy(93.33%vs 75.00%,P=0.006).Leveraging TCM’s five-element theory and Ziwu Liuzhu timing,the intervention targets key acupoints such as Zusanli(ST36)with a herbal paste comprising Qingpi,Houpu,and rhubarb,delivered transdermally to optimize bioavailability.This approach harmonizes ancient TCM principles with contemporary evidence-based practice,offering a holistic strategy to address postoperative nausea,delayed motility,and patient discomfort.Currently,integrative methods like MFI-TEAS are gaining traction,supported by recent meta-analyses that affirm TEAS’s efficacy in accelerating GI recovery across surgical contexts,including shortened times to first exhaust and defecation.This reflects a growing recognition of TCM’s role in perioperative care amidst rising global endoscopy demands.Looking forward,future research should prioritize multicenter,doubleblinded trials to enhance generalizability,adhere to standardized reporting frameworks such as CONSORT and STRICTA,and employ advanced tools like multiomics and functional magnetic resonance imaging to elucidate mechanistic pathways,including gut-brain axis modulation and microbiota-immune interactions.Such developments promise to refine these interventions,fostering a seamless integration of TCM with Western medicine and delivering tailored,patientcentered solutions to improve postoperative outcomes worldwide. 展开更多
关键词 Traditional Chinese medicine Transcutaneous electrical acupoint stimulation Postoperative recovery Gastroenteroscopy Integrative medicine
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Neuronal swelling implicated in functional recovery after spinal cord injury
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作者 Qiang Li 《Neural Regeneration Research》 2026年第4期1558-1559,共2页
Spinal cord injury(SCI) often results in permanent dysfunction of locomotion,sensation,and autonomic regulation,imposing a substantial burden on both individuals and society(Anjum et al.,2020).SCI has a complex pathop... Spinal cord injury(SCI) often results in permanent dysfunction of locomotion,sensation,and autonomic regulation,imposing a substantial burden on both individuals and society(Anjum et al.,2020).SCI has a complex pathophysiology:an initial primary injury(mechanical trauma,axonal disruption,and hemorrhage) is followed by a progressive secondary injury cascade that involves ischemia,neuronal loss,and inflammation.Given the challenges in achieving regeneration of the injured spinal cord,neuroprotection has been at the forefront of clinical research. 展开更多
关键词 spinal cord injury SENSATION neuronal swelling autonomic regulation functional recovery PATHOPHYSIOLOGY spinal cord injury sci locomotion
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Neuromodulation technologies improve functional recovery after brain injury:From bench to bedside
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作者 Mei Liu Yijing Meng +4 位作者 Siguang Ouyang Meng’ai Zhai Likun Yang Yang Yang Yuhai Wang 《Neural Regeneration Research》 2026年第2期506-520,共15页
Spontaneous recovery frequently proves maladaptive or insufficient because the plasticity of the injured adult mammalian central nervous system is limited.This limited plasticity serves as a primary barrier to functio... Spontaneous recovery frequently proves maladaptive or insufficient because the plasticity of the injured adult mammalian central nervous system is limited.This limited plasticity serves as a primary barrier to functional recovery after brain injury.Neuromodulation technologies represent one of the fastest-growing fields in medicine.These techniques utilize electricity,magnetism,sound,and light to restore or optimize brain functions by promoting reorganization or long-term changes that support functional recovery in patients with brain injury.Therefore,this review aims to provide a comprehensive overview of the effects and underlying mechanisms of neuromodulation technologies in supporting motor function recovery after brain injury.Many of these technologies are widely used in clinical practice and show significant improvements in motor function across various types of brain injury.However,studies report negative findings,potentially due to variations in stimulation protocols,differences in observation periods,and the severity of functional impairments among participants across different clinical trials.Additionally,we observed that different neuromodulation techniques share remarkably similar mechanisms,including promoting neuroplasticity,enhancing neurotrophic factor release,improving cerebral blood flow,suppressing neuroinflammation,and providing neuroprotection.Finally,considering the advantages and disadvantages of various neuromodulation techniques,we propose that future development should focus on closed-loop neural circuit stimulation,personalized treatment,interdisciplinary collaboration,and precision stimulation. 展开更多
关键词 functional recovery invasive electrical stimulation NEUROMODULATION noninvasive electrical stimulation stroke transcranial magnetic stimulation transcranial photobiomodulation transcranial ultrasound stimulation traumatic brain injury
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Grafts of hydrogel-embedded electrically stimulated subventricular stem cells into the stroke cavity improves functional recovery of mice
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作者 Andreea-Mihaela Cercel Ianis KS Boboc +5 位作者 Roxana Surugiu Thorsten R.Doeppner Dirk M.Hermann Bogdan Catalin Andrei Gresita Aurel Popa-Wagner 《Neural Regeneration Research》 2026年第2期695-703,共9页
The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly f... The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly formed neurons to the damaged area.However,only a small percentage of these neurons survive,and many do not reach the damaged area,possibly because the corpus callosum impedes the migration of subventricular zone-derived stem cells into the lesioned cortex.A second major obstacle to stem cell therapy is the strong inflammatory reaction induced by cerebral ischemia,whereby the associated phagocytic activity of brain macrophages removes both therapeutic cells and/or cell-based drug carriers.To address these issues,neurogenesis was electrically stimulated in the subventricular zone,followed by isolation of proliferating cells,including newly formed neurons,which were subsequently mixed with a nutritional hydrogel.This mixture was then transferred to the stroke cavity of day 14 post-stroke mice.We found that the performance of the treated animals improved in behavioral tests,including novel object,open field,hole board,grooming,and“time-to-feel”adhesive tape tests.Furthermore,immunostaining revealed that the stem cell marker nestin,the neuroepithelial marker Mash1,and the immature neuronal marker doublecortin-positive cells survived in the transplanted area for 2 weeks,possibly due to reduced phagocytic activity and supportive angiogenesis.These results clearly indicate that the transplantation of committed subventricular zone stem cells combined with a protective nutritional gel directly into the infarct cavity after the peak of stroke-induced neuroinflammation represents a feasible approach to improve neurorestoration after cerebral ischemia. 展开更多
关键词 ANXA3 behavioral recovery DOUBLECORTIN electrical stimulation Mash1 NESTIN STROKE subventricular neural stem cells supportive hydrogel vascular cell adhesion molecule 1
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Differential plasticity of excitatory and inhibitory reticulospinal fibers after spinal cord injury:Implication for recovery
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作者 Rozaria Jeleva Carmen Denecke Muhr +1 位作者 Alina P.Liebisch Florence M.Bareyre 《Neural Regeneration Research》 2026年第5期2011-2020,共10页
The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory ... The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory fibers.While the reticulospinal tract has been shown to be particularly prone to axonal growth and plasticity following injuries of the spinal cord,the differential capacities of excitatory and inhibitory fibers for plasticity remain unclear.As adaptive axonal plasticity involves a sophisticated interplay between excitatory and inhibitory input,we investigated in this study the plastic potential of glutamatergic(vGlut2)and GABAergic(vGat)fibers originating from the gigantocellular nucleus and the lateral paragigantocellular nucleus,two nuclei important for locomotor function.Using a combination of viral tracing,chemogenetic silencing,and AI-based kinematic analysis,we investigated plasticity and its impact on functional recovery within the first 3 weeks following injury,a period prone to neuronal remodeling.We demonstrate that,in this time frame,while vGlut2-positive fibers within the gigantocellular and lateral paragigantocellular nuclei rewire significantly following cervical spinal cord injury,vGat-positive fibers are rather unresponsive to injury.We also show that the acute silencing of excitatory axonal fibers which rewire in response to lesions of the spinal cord triggers a worsening of the functional recovery.Using kinematic analysis,we also pinpoint the locomotion features associated with the gigantocellular nucleus or lateral paragigantocellular nucleus during functional recovery.Overall,our study increases the understanding of the role of the gigantocellular and lateral paragigantocellular nuclei during functional recovery following spinal cord injury. 展开更多
关键词 GABAergic(vGat)fibers gait features glutamatergic(vGlut2)fibers PLASTICITY recovery of function reticulospinal tract spinal cord injury
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N-S EQUATION CALCULATIONS ON MULTI-ELEMENT AIRFOILS WITH ZONAL PATCHED GRIDS 被引量:2
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作者 郭同庆 陆志良 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期155-158,共4页
For a complex flow about multi-element airfoils a mixed grid method is set up. C-type grids are produced on each element′s body and in their wakes at first, O-type grids are given in the outmost area, and H-type grid... For a complex flow about multi-element airfoils a mixed grid method is set up. C-type grids are produced on each element′s body and in their wakes at first, O-type grids are given in the outmost area, and H-type grids are used in middle additional areas. An algebra method is used to produce the initial grids in each area. And the girds are optimized by elliptical differential equation method. Then C-O-H zonal patched grids around multi-element airfoils are produced automatically and efficiently. A time accurate finite-volume integration method is used to solve the compressible laminar and turbulent Navier-Stokes (N-S) equations on the grids. Computational results prove the method to be effective. 展开更多
关键词 multi-element airfoils zonal patched grids finite-volume method N-S equations
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Optimization of multi-element airfoil settings considering ice accretion effect 被引量:5
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作者 Jinzhao DAI Haoran LI +1 位作者 Yufei ZHANG Haixin CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第2期41-57,共17页
Almost half of all flight accidents caused by inflight icing occur at the approach and landing phases when high-lift devices are deployed.The present study focuses on the optimization of an ice-tolerant multi-element ... Almost half of all flight accidents caused by inflight icing occur at the approach and landing phases when high-lift devices are deployed.The present study focuses on the optimization of an ice-tolerant multi-element airfoil.Dual-objective optimization is carried out with critical hornshaped ice accumulated during the holding phase.The optimization results show that the present optimization method significantly enhances the iced-state and clean-state performance.The optimal multi-element airfoil has a larger deflection angle and wider gap at the slat and the flap compared with the baseline configuration.The sensitivity of each design parameter is analyzed,which verifies the robustness of the design.The design is further assessed when ice is accreted during the approach and landing phases,which also shows performance improvement. 展开更多
关键词 Aircraft icing AIRLINER Ice-tolerant airfoil multi-element airfoil Optimization design
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Monte Carlo simulation of reflection effects of multi-element materials on gamma rays 被引量:5
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作者 Ying-Hong Zuo Jin-Hui Zhu Peng Shang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第1期85-94,共10页
To study the effects of the gamma reflection of multi-element materials,gamma ray transport models of single-element materials,such as iron and lead,and multielement materials,such as polyethylene and ordinary concret... To study the effects of the gamma reflection of multi-element materials,gamma ray transport models of single-element materials,such as iron and lead,and multielement materials,such as polyethylene and ordinary concrete,were established in this study.Relationships among the albedo factors of the gamma photons and energies and average energy of the reflected gamma rays by material type,material thickness,incident gamma energy,and incidence angle of gamma rays were obtained by Monte Carlo simulation.The results show that the albedo factors of single-element and multi-element materials increase rapidly with an increase in the material thickness.When the thickness of the material increases to a certain value,the albedo factors do not increase further but rather tend to the saturation value.The saturation values for the albedo factors of the gamma photons,and energies and the reflection thickness are related not only to the type of material but also to the incident gamma energy and incidence angle of the gamma rays.At a given incident gamma energy,which is between 0.2 and 2.5 MeV,the smaller the effective atomic number of the multi-element material is,the higher the saturation values of the albedo factors are.The larger the incidence angle of the gamma ray is,the greater the saturation value of the gamma albedo factor,saturation reflection thickness,and average saturation energy of the reflected gamma photons are. 展开更多
关键词 multi-element materials Gamma albedo factor Effective atomic number Monte Carlo simulation
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Aerodynamic and Acoustic Optimization for Multi-element Airfoils 被引量:1
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作者 Deng Yiju Duan Zhuoyi Liu Xueqiang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第4期683-692,共10页
The paper is to integrate aerodynamic and aero-acoustic optimizatiom design of high lift devices,especially for two-element airfoils with slat.Aerodynamic analysis on flow field utilizes a high-order,high-resolution s... The paper is to integrate aerodynamic and aero-acoustic optimizatiom design of high lift devices,especially for two-element airfoils with slat.Aerodynamic analysis on flow field utilizes a high-order,high-resolution spatial differential method for large eddy simulation(LES),which can guarantee accuracy and efficiency.The aeroacoustic analysis for noise level is calculated with Ffowcs Williams-Hawkings(FW-H)integration formula.Fidelity of calculation is verified by standard models.Method of streamline-based Euler simulation(MSES)is used to obtain the aerodynamic characters.Based on the confirmation of numerical methods,detailed research has been conducted for the leading edge slat on multi-element airfoils.Various slot parameter influences on noise are analyzed.The results of the slot optimization parameters can be used in multi-element airfoil design. 展开更多
关键词 slat multi-element airfoil aero-acoustic OPTIMIZATION
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Effect of Al and Sc on deformation behavior of FeCoNi multi-element alloys 被引量:1
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作者 Rui ZHOU Mou LI +4 位作者 Jing-wen QIU Si-hui OUYANG Di PAN Cheng-shang ZHOU Yong LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第10期2109-2116,共8页
The effects of Al and Sc on mechanical properties of FeCoNi multi-element alloys(MEAs) were investigated by compressive tests. The microstructures of FeCoNi MEAs with different contents of Al and Sc were characterized... The effects of Al and Sc on mechanical properties of FeCoNi multi-element alloys(MEAs) were investigated by compressive tests. The microstructures of FeCoNi MEAs with different contents of Al and Sc were characterized and the strengthening mechanisms were discussed. The results show that FeCoNi MEA with a low content of Al has a face-centered cubic(FCC) structure. The yield strength increases linearly with the increase of Al content, which is largely caused by solid solution hardening. Further addition of Sc can promote the formation of a new phase in(FeCoNi)1-xAlx MEAs. A minor addition of Sc can significantly increase the yield strengths of(FeCoNi)1-xAlx MEAs with a low Al content and improve the compressive plasticity of(FeCoNi)1-xAlx MEAs with a high Al content. 展开更多
关键词 FeCoNi multi-element alloys mechanical properties MICROSTRUCTURE strengthening mechanism
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A DDoS Attack Information Fusion Method Based on CNN for Multi-Element Data 被引量:1
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作者 Jieren Cheng Canting Cai +3 位作者 Xiangyan Tang Victor SSheng Wei Guo Mengyang Li 《Computers, Materials & Continua》 SCIE EI 2020年第4期131-150,共20页
Traditional distributed denial of service(DDoS)detection methods need a lot of computing resource,and many of them which are based on single element have high missing rate and false alarm rate.In order to solve the pr... Traditional distributed denial of service(DDoS)detection methods need a lot of computing resource,and many of them which are based on single element have high missing rate and false alarm rate.In order to solve the problems,this paper proposes a DDoS attack information fusion method based on CNN for multi-element data.Firstly,according to the distribution,concentration and high traffic abruptness of DDoS attacks,this paper defines six features which are respectively obtained from the elements of source IP address,destination IP address,source port,destination port,packet size and the number of IP packets.Then,we propose feature weight calculation algorithm based on principal component analysis to measure the importance of different features in different network environment.The algorithm of weighted multi-element feature fusion proposed in this paper is used to fuse different features,and obtain multi-element fusion feature(MEFF)value.Finally,the DDoS attack information fusion classification model is established by using convolutional neural network and support vector machine respectively based on the MEFF time series.Experimental results show that the information fusion method proposed can effectively fuse multi-element data,reduce the missing rate and total error rate,memory resource consumption,running time,and improve the detection rate. 展开更多
关键词 DDoS attack multi-element data information fusion principal component analysis CNN
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Identifying Pathfinder Elements for Gold in Multi-Element Soil Geochemical Data from the Wa-Lawra Belt, Northwest Ghana: A Multivariate Statistical Approach 被引量:2
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作者 Prosper Mackenzie Nude John Mahfouz Asigri +3 位作者 Sandow Mark Yidana Emmanuel Arhin Gordon Foli Jacob Mawuko Kutu 《International Journal of Geosciences》 2012年第1期62-70,共9页
A multivariate statistical analysis was performed on multi-element soil geochemical data from the Koda Hill-Bulenga gold prospects in the Wa-Lawra gold belt, northwest Ghana. The objectives of the study were to define... A multivariate statistical analysis was performed on multi-element soil geochemical data from the Koda Hill-Bulenga gold prospects in the Wa-Lawra gold belt, northwest Ghana. The objectives of the study were to define gold relationships with other trace elements to determine possible pathfinder elements for gold from the soil geochemical data. The study focused on seven elements, namely, Au, Fe, Pb, Mn, Ag, As and Cu. Factor analysis and hierarchical cluster analysis were performed on the analyzed samples. Factor analysis explained 79.093% of the total variance of the data through three factors. This had the gold factor being factor 3, having associations of copper, iron, lead and manganese and accounting for 20.903% of the total variance. From hierarchical clustering, gold was also observed to be clustering with lead, copper, arsenic and silver. There was further indication that, gold concentrations were lower than that of its associations. It can be inferred from the results that, the occurrence of gold and its associated elements can be linked to both primary dispersion from underlying rocks and secondary processes such as lateritization. This data shows that Fe and Mn strongly associated with gold, and alongside Pb, Ag, As and Cu, these elements can be used as pathfinders for gold in the area, with ferruginous zones as targets. 展开更多
关键词 MULTIVARIATE Analyses multi-elements SOIL Geochemical Data PATHFINDER ELEMENTS GOLD NORTHWEST Ghana
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Understory Recovery in Coast Redwood Communities: A Case Study Comparing a Naturally Recovering and an Actively Managed Forest 被引量:1
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作者 Alyssa Hanover Will Russell 《Open Journal of Forestry》 2018年第4期489-499,共11页
Restoration of late seral features in second growth Sequoia sempervirens (coast redwood) forests is increasingly important, as so little of the original old-growth remains. Natural recovery is an effective method rest... Restoration of late seral features in second growth Sequoia sempervirens (coast redwood) forests is increasingly important, as so little of the original old-growth remains. Natural recovery is an effective method restoring many late seral features, and does not require the additional disturbance of active management. In order to better understand management impacts on redwood understory abundance and composition, data were collected in naturally recovering stands and in stands that were actively managed with the explicit intent of promoting old-growth characteristics. Ten 10 m diameter plots with three 2 m diameter nested sub-plots were randomly sampled in two sites within each management type. Results indicate that tree canopy cover, native species cover and richness, richness of coast redwood associated species, and the cover of Trillium ovatum (western wake robin) were significantly higher in naturally recovering versus actively managed stands. In addition, several coast redwood associated understory species were exclusively recorded in the naturally recovering stands including: Asuram caudatum (wild ginger), Prosartes hookeri (hooker’s fairybells), Maianthemum racemosum (false solomon seal), Scoliopus bigelovii (fetid adder’s tongue), Viola sempervirens (redwood violet);while only one such species was recorded exclusively in the actively managed stands: Trientalis latifolia (pacific star flower). Natural recovery appeared to support understory recovery more effectively than active forest management in this case. 展开更多
关键词 Restoration Natural recovery Active Management OLD-GROWTH Late-Seral
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Exploratory Data Analysis Applied in Mapping Multi-element Soil Geochemical Anomalies for Drill Target Definition:A Case Study from the Unpha Layered Non-magmatic Hydrothermal Pb-Zn Deposit,DPR Korea
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作者 JANG Gwang-Hyok WON Hyon-Chol +1 位作者 HWANG Bo-Hyon CHOI Chol-Man 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第4期1357-1365,共9页
A factor analysis was applied to soil geochemical data to define anomalies related to buried Pb-Zn mineralization.A favorable main factor with a strong association of the elements Zn,Cu and Pb,related to mineralizatio... A factor analysis was applied to soil geochemical data to define anomalies related to buried Pb-Zn mineralization.A favorable main factor with a strong association of the elements Zn,Cu and Pb,related to mineralization,was selected for interpretation.The median+2 MAD(median absolute deviation)method of exploratory data analysis(EDA)and C-A(concentration-area)fractal modeling were then applied to the Mahalanobis distance,as defined by Zn,Cu and Pb from the factor analysis to set the thresholds for defining multi-element anomalies.As a result,the median+2 MAD method more successfully identified the Pb-Zn mineralization than the C-A fractal model.The soil anomaly identified by the median+2 MAD method on the Mahalanobis distances defined by three principal elements(Zn,Cu and Pb)rather than thirteen elements(Co,Zn,Cu,V,Mo,Ni,Cr,Mn,Pb,Ba,Sr,Zr and Ti)was the more favorable reflection of the ore body.The identified soil geochemical anomalies were compared with the in situ economic Pb-Zn ore bodies for validation.The results showed that the median+2 MAD approach is capable of mapping both strong and weak geochemical anomalies related to buried Pb-Zn mineralization,which is therefore useful at the reconnaissance drilling stage. 展开更多
关键词 factor analysis exploratory data analysis Mahalanobis distance multi-element Unpha
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Geochemical analysis of multi-element in archaeological soils from Tappe Rivi in Northeast Iran
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作者 Abdulmannan Rouhani Hamidreza Azimzadeh +2 位作者 Ahad Sotoudeh Judith Thomalsky Hojat Emami 《Acta Geochimica》 EI CAS CSCD 2022年第1期132-146,共15页
Multi-element analysis in historical sites is a major issue in archaeological studies;however,this approach is almost unknown among Iranian scholars.Geochemical multi-element analysis of soil is very important to eval... Multi-element analysis in historical sites is a major issue in archaeological studies;however,this approach is almost unknown among Iranian scholars.Geochemical multi-element analysis of soil is very important to evaluate anthropogenic activities.The aim of this study consists of assessing the potential usefulness of multi-elemental soil analysis,obtained by Analytical Jena atomic absorption spectrophotometer(AAS) and ICP-MS,to recognize ancient anthropogenic features on the territory of Tappe Rivi(North Khorasan,Iran).For that purpose,a total of 80 ancient soil samples were sampled from each soil horizon and cultural layer.The research involved Fe,Al,Cd,Cu,Ni,Co,Cr,Pb,and P which trace element samples were extracted according to the International Standard ISO 11466 and phosphorus samples by Olsen method.Besides,the contamination of the soils was assessed based on enrichment factors(EFs) by using Fe as a reference element.This geochemical/archaeological approach highlights that the content of most elements in the Parthian and Sassanid ages were significantly higher than the contents of the elements in other zones,which shows that by the development of the eras,the content of the elements has also increased.Also,the accumulation of metals in the Rivi site was significantly higher than in the control area.Among the sampled zones,enrichment factor(EF) indicated that the enrichment of Cu and phosphate at the Parthian and Sassanid had the highest content.This result is important because it shows that the amount of metals and human activities are directly related to each other during different ages. 展开更多
关键词 Tappe Rivi multi-element PHOSPHORUS Ancient human impact Samalghan plain
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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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HYBRID CARTESIAN GRID/GRIDLESS METHOD FOR CALCULATING VISCOUS FLOWS OVER MULTI-ELEMENT AIRFOILS
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作者 蒲赛虎 陈红全 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第3期232-236,共5页
A hybrid Cartesian grid/gridless method is developed for calculating viscous flows over multi-element airfoils.The method adopts an unstructured Cartesian grid to cover most areas of the computational domain and leave... A hybrid Cartesian grid/gridless method is developed for calculating viscous flows over multi-element airfoils.The method adopts an unstructured Cartesian grid to cover most areas of the computational domain and leaves only small region adjacent to the aerodynamic bodies to be filled with the cloud of points used in the gridless methods,which results in a better combination of the computational efficiency of the Cartesian grid and the flexibility of the gridless method in handling complex geometries.The clouds of points in the local gridless region are implemented in an anisotropic way according to the features of the thin boundary layer of the viscous flows over the airfoils,and the clouds of points at the vicinity of the interface between the grid and the gridless regions are also controlled by using an adaptive refinement technique during the generation of the unstructured Cartesian grid.An implementation of the resulting hybrid method is presented for solving two-dimensional compressible Navier-Stokes(NS)equations.The simulations of the viscous flows over a RAE2822airfoil or a two-element airfoil are successfully carried out,and the obtained results agree well with the available experimental data. 展开更多
关键词 multi-element airfoil gridless method Cartesian grid viscous flow NS equations
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Experiments of Multi-element Composite Foundation with Steel Pipe Pile and Gravel Pile
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作者 王仙芝 郑俊杰 《Journal of Southwest Jiaotong University(English Edition)》 2008年第3期254-259,共6页
A set of serf-developed apparatus for foundation physical model were utilized to conduct model tests of the multi-element composite foundation with a steel pipe pile and several gravel piles. Some load-bearing charact... A set of serf-developed apparatus for foundation physical model were utilized to conduct model tests of the multi-element composite foundation with a steel pipe pile and several gravel piles. Some load-bearing characteristics of the multi-element Composite foundation, including the curves of foundation settlement, stresses of piles, pile-soil stress ratio, and load-sharing ratio of piles and soil, were obtained to study its working performances in silty sand soil. The experimental results revealed that the multi-element composite foundation with steel pipe pile and gravel pile contributed more than the gravel pile composite foundation in improving the bearing capacity of the silty fine sand. 展开更多
关键词 Steel pipe pile Gravel pile Model test multi-element composite foundation Pile-soil stress ratio Load-sharing ratio
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