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Activating d^(10)electronic configuration to regulate p-band centers as efficient active sites for solar energy conversion into H_(2)by surface atomic arrangement
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作者 Shanshan Lai Jiakun Su +2 位作者 Shujuan Jiang Jianjun Zhang Shaoqing Song 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期185-194,共10页
Relationship between the activity for photocatalytic H_(2)O overall splitting(HOS)and the electron occupancy on d orbits of the active component in photocatalysts shows volcanic diagram,and specially the d^(10)electro... Relationship between the activity for photocatalytic H_(2)O overall splitting(HOS)and the electron occupancy on d orbits of the active component in photocatalysts shows volcanic diagram,and specially the d^(10)electronic configuration in valley bottom exhibits inert activity,which seriously fetters the development of catalytic materials with great potentials.Herein,In d^(10)electronic configuration of In_(2)O_(3)was activated by phosphorus atoms replacing its lattice oxygen to regulate the collocation of the ascended In 5p-band(Inɛ5p)and descended O 2p-band(Oɛ2p)centers as efficient active sites for chemisorption to*OH and*H during forward HOS,respectively,along with a declined In 4d-band center(Inɛ4d)to inhibit its backward reaction.A stable STH efficiency of 2.23%under AM 1.5 G irradiation at 65°C has been obtained over the activated d^(10)electronic configuration with a lowered activation energy for H_(2)evolution,verified by femtosecond transient absorption spectroscopy,in situ diffuse reflectance infrared Fourier transform spectroscopy and theoretical calculations of dynamics.These findings devote to activating d^(10)electronic configuration for resolving the reaction energy barrier and dynamical bottleneck of forward HOS,which expands the exploration of high-efficiency catalytic materials. 展开更多
关键词 d-Band center p-Band center Localized field Photocatalytic water splitting Dynamic process
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Effect of sintering temperature and holding time on structure and properties of Li_(1.5)Ga_(0.5)Ti_(1.5)(PO_4)_(3)electrolyte with fast ionic conductivity
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作者 Yin-yi LUO Hao-zhang LIANG +6 位作者 Ping ZHANG Lei HAN Qian ZHANG Li-dan LIU Zhi-wei LUO Tian-xiang NING An-xian LU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2959-2971,共13页
Li_(1.5)Ga_(0.5)Ti_(1.5)PO_(4))_(3)(LGTP)is recognized as a promising solid electrolyte material for lithium ions.In this work,LGTP solid electrolyte materials were prepared under different process conditions to explo... Li_(1.5)Ga_(0.5)Ti_(1.5)PO_(4))_(3)(LGTP)is recognized as a promising solid electrolyte material for lithium ions.In this work,LGTP solid electrolyte materials were prepared under different process conditions to explore the effects of sintering temperature and holding time on relative density,phase composition,microstructure,bulk conductivity,and total conductivity.In the impedance test under frequency of 1-10^(6) Hz,the bulk conductivity of the samples increased with increasing sintering temperature,and the total conductivity first increased and then decreased.SEM results showed that the average grain size in the ceramics was controlled by the sintering temperature,which increased from(0.54±0.01)μm to(1.21±0.01)μm when the temperature changed from 750 to 950°C.The relative density of the ceramics increased and then decreased with increasing temperature as the porosity increased.The holding time had little effect on the grain size growth or sample density,but an extended holding time resulted in crack generation that served to reduce the conductivity of the solid electrolyte. 展开更多
关键词 sintering temperature holding time CONDUCTIVITY cracks solid-state electrolyte
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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders
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作者 Victor V.Chizhikov Igor Y.Iskusnykh 《Neural Regeneration Research》 SCIE CAS 2025年第4期1079-1080,共2页
Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,... Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in mice.The cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)proteins.The cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022). 展开更多
关键词 EPITHELIUM FIGURE center
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Preparing highly entangled states of nanodiamond rotation and NV center spin
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作者 李文亮 周端陆 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期144-151,共8页
A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical r... A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical rotation of the nanodiamond plays a fundamental role in building a quantum network connecting these microscopic and mesoscopic degrees of motions.Here we present a protocol to asymptotically prepare a highly entangled state of the total quantum angular momentum and electron spin by adiabatically boosting the external magnetic field. 展开更多
关键词 NANODIAMOND NV center ENTANGLEMENT
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Prevalence of Enteric Pathogens Associated with Infections among Table Egg Consumers in Some Primary Health Establishments in the Center Region of Cameroon
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作者 Mariane Lucie Ngueguim Bernard Viban Tangwa +2 位作者 Victor Ngu Ngwa Albert Ngakou Abdoulmoumini Mamoudou 《Advances in Infectious Diseases》 CAS 2024年第3期606-619,共14页
Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains o... Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains of stomach disorders after egg consumption. Data related to sociodemographic characteristics and other factors were collected using a structured based questionnaire. Stool culture of utmost importance in stomach disorders patients and serum were collected for typhoid serological test. Results: A total of 207 participants took part in the survey, Results indicated nontyphoidal Salmonella infections were highest in the 3 areas of study with Mfoundi (73.44%) having the highest level of infection compared to other bacterial infection. other enteric bacteria associated to this infection were E. coli serotype 157, Aeromonas, Citrobacter freundii, Enterobacter cloaca and typhi salmonella. Meanwhile salmonelosis caused by typhic salmonella had highest prevalence in the Lekie Division (13.11%) as a result of poor hygienic practices associated with the conservation and preparation of eggs, Stool culture was observed to detect more positive cases in the diagnosis of typhoid fever than Widal test, but with no statistically significant (p > 0.05) difference between the stool culture and Widal test in the 3 areas of study. Conclusion: this study revealed that egg consumers are pruned to enteric bacterial and salmonella infections depending on how and where egg is consumed. 展开更多
关键词 Enteric Pathogens Table Eggs Consumption center Region Cameroon
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The Peripheral Hospital as Focal Point for Pacemaker Activity: Review of the Last 300 Implantations Carried out at the Haute Correze Hospital Center
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作者 Mazou Temgoua Alain Berenfeld +1 位作者 Lionel Blasco Benoit Guy-Moyat 《World Journal of Cardiovascular Diseases》 CAS 2024年第9期547-556,共10页
Background: Pacemaker implantation is a very old activity which has revolutionized the cardiology practice throughout the world. This activity is effective at the Haute Correze Hospital Center since more than 20 years... Background: Pacemaker implantation is a very old activity which has revolutionized the cardiology practice throughout the world. This activity is effective at the Haute Correze Hospital Center since more than 20 years. Due to progress in this area, and the increasing request within this center located at the outskirts of town, we set out to evaluate our pacemaker activity in general and more specifically to assess the post-procedural complications in our series patients. Methodology: This was a retrospective longitudinal study. Data were recorded for period of 90 months from 27/05/2016 to 19/11/2023. This data collection was possible via a specific register completed by computerized patient data from the SillageTM software. All files of patients implanted with single or dual chamber pacemakers were included, generator replacements, upgrading procedures and addition of leads were excluded. The sampling was non-probabilistic, consecutive and non-exhaustive. Statistical analysis was carried out using the Excel 2019 spreadsheet and SPSS version 23 software. The quantitative variables were presented as mean ± standard deviation, the qualitative data as proportions. Results: A total of 303 first-time pacemaker’s implantations were carried out during the study period (rate of 40 per year). The average age in the population was 79.7 ± 9.4 years (44 - 99 years) with a male predominance of 63.7% (n = 193). Atrioventricular block (2nd and 3rd degree) was the main indication for pacemaker implantation in 42.9% of cases (n = 130). Patients were most often implanted with a dual-chamber pacemaker (57.7%, n = 175). The approach was most often cephalic in 72.6% of cases (n = 220), followed by the subclavian access in 27.4% of cases (n = 84). The average fluoroscopy time was 7.9 min ± 2.4 (1 - 43). The average irradiation dose in gray/cm2 was 12.4 ± 9.3 (0.22 - 117.5). The average length of hospitalization was 7 ± 4 (2 - 26) days. The overall complication rate at one year was 12.9% (n = 39). These complications are distributed as follows: Leads dislodgement in 8.2% (n = 25), hematoma 3.6% (n = 11) all without clinical consequences, pneumothorax 0.7% (n = 2), both cases of pneumothorax did not require specific care, infection (superficial) in 0.3% (n = 1). Leads dislodgement occurred after a median time of 18 days (IQR: 3 - 36). The earliest dislodgement was observed on D0 and the latest on D207. No serious complications were recorded. The average atrial threshold at implantation/first control/last follow-up was 0.7/1.3/0.8 V, respectively. The average ventricular threshold at implantation/first control/last follow-up was 0.5/1.08/0.87 V, respectively. The average atrial detection at implantation/first control/last follow-up was 3.2/2.3/ 2.05 mv, respectively. The average ventricular detection at implantation/first control/last follow-up was 10.3/11.03/10.8 mv. The average atrial impedance at implantation/first control/last follow-up was 610/457/457 ohms. The average ventricular impedance at implantation/first control/last follow-up was 754/547/563 ohms. Conclusion: Pacemaker implantation is safe at the Haute Correze Hospital Center with a relatively low rate of complications, in this case an almost zero major infection and no serious hematoma. The peripheral hospital should remain a focal point of this activity in order to respond more quickly to the needs of the populations. 展开更多
关键词 Peripheral Hospital PACEMAKER Haute Correze Hospital center
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Comment on“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”
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作者 Xiang-Yan Liu Yun-Yang Xu +1 位作者 Ze Xiang Shu-Sen Zheng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第1期109-110,共2页
To the Editor:We read with great interest the article by Schulze et al.entitled“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”[1].It is the first single-cent... To the Editor:We read with great interest the article by Schulze et al.entitled“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”[1].It is the first single-center report including over 500 fully robotic donor hepatectomies.For the donors,the overall complication rate was 6.4%(n=32).Postoperative self-limiting bleeding(0.4%)and bile leakage from the resection plane(1.8%)were rare. 展开更多
关键词 ROBOTIC ROBOTIC center
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Impacts of bus holding strategy on the performance and pollutant emissions of a two-lane mixed traffic system
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作者 Yanfeng Qiao Ronghan Yao +1 位作者 Baofeng Pan Yu Xue 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期236-248,共13页
This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissio... This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissions of passenger cars.The dynamic behaviors of these two types of vehicles are described using cellular automata(CA)models under open boundary conditions.Numerical simulations are carried out to obtain the phase diagrams of the bus system and the trajectories of buses and passenger cars before and after the implementation of the bus holding strategy under different probabilities of passenger cars entering a two-lane mixed traffic system.Then,we analyze the flow rate,satisfaction rate,and pollutant emission rates of passenger cars together with the performance of a mixed traffic system.The results show that the bus holding strategy can effectively alleviate bus bunching,whereas it has no significant impact on the flow rate and pollutant emission rates of passenger cars;the flow rate,satisfaction rate,and pollutant emission rates of passenger cars for either the traffic system or for each lane are influenced by the bus departure interval and the number of passengers arriving at bus stops. 展开更多
关键词 mixed traffic flow bus holding strategy cellular automata traffic emissions
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Dynamic Routing of Multiple QoS-Required Flows in Cloud-Edge Autonomous Multi-Domain Data Center Networks
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作者 Shiyan Zhang Ruohan Xu +3 位作者 Zhangbo Xu Cenhua Yu Yuyang Jiang Yuting Zhao 《Computers, Materials & Continua》 SCIE EI 2024年第2期2287-2308,共22页
The 6th generation mobile networks(6G)network is a kind of multi-network interconnection and multi-scenario coexistence network,where multiple network domains break the original fixed boundaries to form connections an... The 6th generation mobile networks(6G)network is a kind of multi-network interconnection and multi-scenario coexistence network,where multiple network domains break the original fixed boundaries to form connections and convergence.In this paper,with the optimization objective of maximizing network utility while ensuring flows performance-centric weighted fairness,this paper designs a reinforcement learning-based cloud-edge autonomous multi-domain data center network architecture that achieves single-domain autonomy and multi-domain collaboration.Due to the conflict between the utility of different flows,the bandwidth fairness allocation problem for various types of flows is formulated by considering different defined reward functions.Regarding the tradeoff between fairness and utility,this paper deals with the corresponding reward functions for the cases where the flows undergo abrupt changes and smooth changes in the flows.In addition,to accommodate the Quality of Service(QoS)requirements for multiple types of flows,this paper proposes a multi-domain autonomous routing algorithm called LSTM+MADDPG.Introducing a Long Short-Term Memory(LSTM)layer in the actor and critic networks,more information about temporal continuity is added,further enhancing the adaptive ability changes in the dynamic network environment.The LSTM+MADDPG algorithm is compared with the latest reinforcement learning algorithm by conducting experiments on real network topology and traffic traces,and the experimental results show that LSTM+MADDPG improves the delay convergence speed by 14.6%and delays the start moment of packet loss by 18.2%compared with other algorithms. 展开更多
关键词 MULTI-DOMAIN data center networks AUTONOMOUS ROUTING
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Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment
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作者 Ntombela N. Lethukuthula Mathuthu Manny Nyathi Mpumelelo 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第3期41-52,共12页
The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatme... The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery. 展开更多
关键词 Breast Cancer Deep Inspiration Breath hold Hypo-Fractionation Inter-Fraction
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Management of Acute Malnutrition in Children Aged 0 to 24 Months Boulbinet Health Center
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作者 Mohamed Lamine Diallo Mamadou Ciré Barry +4 位作者 M’mah Aminata Bangoura Louis Philippe Diffo Mamadouba Bangoura Fatoumata Sacko Telly Sy 《Open Journal of Pediatrics》 2024年第1期122-131,共10页
Introduction: Malnutrition is a pathological state resulting from the relative deficiency or excess of one or more essential nutrients, whether manifested clinically or detected only by biochemical, anthropometric or ... Introduction: Malnutrition is a pathological state resulting from the relative deficiency or excess of one or more essential nutrients, whether manifested clinically or detected only by biochemical, anthropometric or physiological analyses. The overall objective was to assess the quality of management of acute malnutrition in children aged 0 - 24 months at the Boulbinet health center. Methodology: This was a prospective descriptive study lasting six (06) months from May 5 to October 5, 2018. The study included all children aged 0 to 24 months. Results: Acute malnutrition in children aged 0 - 24 months accounted for 2.11% of cases. The sex ratio was 1.41 in favor of males. The mean age of our patients was 5 months 7 days, with extremes of 1 month and 6 months. The majority came from Ra toma (40.24%). Exclusive breastfeeding was most common (54.02%). The main clinical signs were: pallor 49.42%, diarrhea 46.67, oral lesions37.96%. SAM represented 89.66% and MAM 10.34%. Most associated pathologies: anemia 49.42% and oral candidiasis 37.93%. In terms of outcome, we recorded 56.32% cures, 20.69% deaths, 18.39% dropouts and 4.60% cures. Conclusion: Improving the quality of care for malnourished children aged 0 - 24 months requires raising awareness among mothers and the general public of the consequences of malnutrition. 展开更多
关键词 MANAGEMENT Acute Malnutrition center Boulbinet
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Introducing hydroxyl groups to tailor the d-band center of Ir atom through side anchoring for boosted ORR and HER
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作者 Qing Lv Meiping Li +3 位作者 Xiaodong Li Xingru Yan Zhufeng Hou Changshui Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期144-151,I0005,共9页
Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of... Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of hydrogen-substituted graphdiyne(HsGDY),and coordinated with OH as an Ir atomic catalyst(Ir_(1)-N-HsGDY).The electron structures,especially the d-band center of Ir atom,are optimized by these specific coordination atoms.Thus,the as-synthesized Ir_(1)-N-HsGDY exhibits excellent electrocatalytic performances for oxygen reduction and hydrogen evolution reactions in both acidic and alkaline media.Benefiting from the unique structure of HsGDY,IrN_(2)(OH)_(3) has been developed and demonstrated to act as the active site in these electrochemical reactions.All those indicate the fresh role of the sp-N in graphdiyne in producing a new anchor way and contributing to promote the electrocatalytic activity,showing a new strategy to design novel electrochemical catalysts. 展开更多
关键词 Oxygen reduction reaction D-band center Graphdiyne Hydroxyl group ELECTROCATALYSIS
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Generation of macroscopic entanglement in ensemble systems based on silicon vacancy centers
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作者 Jian-Zhuang Wu Ying Xi +2 位作者 Bo-Ya Li Lian-E Lu Yong-Hong Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期308-315,共8页
Entanglement in macroscopic systems,as a fundamental quantum resource,has been utilized to propel the advancement of quantum technology and probe the boundary between the quantum and classical realms.This study focuse... Entanglement in macroscopic systems,as a fundamental quantum resource,has been utilized to propel the advancement of quantum technology and probe the boundary between the quantum and classical realms.This study focuses on a unique hybrid quantum system comprising of an ensemble of silicon vacancy(SiV)centers coupled to phononic waveguides in diamond via strain interactions.By employing two sets of time-dependent,non-overlapping driving fields,we investigate the generation process and dynamic properties of macroscopic quantum entanglement,providing fresh insights into the behavior of such hybrid quantum systems.Furthermore,it paves the way for new possibilities in utilizing quantum entanglement as an information carrier in quantum information processing and quantum communication. 展开更多
关键词 quantum entanglement silicon vacancy centers diamond waveguide
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Characterization of Hydroxyapatite Extracted from Crab Shell Using the Hydrothermal Method with Varying Holding Times
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作者 Deni Fajar Fitriyana Rifky Ismail +2 位作者 Athanasius Priharyoto Bayuseno Januar Parlaungan Siregar Tezara Cionita 《Journal of Renewable Materials》 EI CAS 2024年第6期1145-1163,共19页
Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_... Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively. 展开更多
关键词 HYDROXYAPATITE crab shells CaCO_(3) HYDROTHERMAL holding time
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An Adaptive Congestion Control Optimization Strategy in SDN-Based Data Centers
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作者 Jinlin Xu Wansu Pan +2 位作者 Haibo Tan Longle Cheng Xiaofeng Li 《Computers, Materials & Continua》 SCIE EI 2024年第11期2709-2726,共18页
The traffic within data centers exhibits bursts and unpredictable patterns.This rapid growth in network traffic has two consequences:it surpasses the inherent capacity of the network’s link bandwidth and creates an i... The traffic within data centers exhibits bursts and unpredictable patterns.This rapid growth in network traffic has two consequences:it surpasses the inherent capacity of the network’s link bandwidth and creates an imbalanced network load.Consequently,persistent overload situations eventually result in network congestion.The Software Defined Network(SDN)technology is employed in data centers as a network architecture to enhance performance.This paper introduces an adaptive congestion control strategy,named DA-DCTCP,for SDN-based Data Centers.It incorporates Explicit Congestion Notification(ECN)and Round-Trip Time(RTT)to establish congestion awareness and an ECN marking model.To mitigate incorrect congestion caused by abrupt flows,an appropriate ECN marking is selected based on the queue length and its growth slope,and the congestion window(CWND)is adjusted by calculating RTT.Simultaneously,the marking threshold for queue length is continuously adapted using the current queue length of the switch as a parameter to accommodate changes in data centers.The evaluation conducted through Mininet simulations demonstrates that DA-DCTCP yields advantages in terms of throughput,flow completion time(FCT),latency,and resistance against packet loss.These benefits contribute to reducing data center congestion,enhancing the stability of data transmission,and improving throughput. 展开更多
关键词 Data centers SDN TCP congestion control RTT ECN
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In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites
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作者 Peng Zhang Fukuan Li +6 位作者 Mingming He Silu Huo Xueli Zhang Benqiang Cen Dezhi Fang Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期126-137,共12页
Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.Howev... Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricfield and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption. 展开更多
关键词 Electro-assisted adsorption ELECTROSORPTION Phosphate removal Active centers MOF-derived carbon
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Design of compact integrated diamond nitrogen-vacancy center quantum probe
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作者 夏圣开 卢文韬 +10 位作者 赵旭彤 薛雅文 许增博 葛仕宇 汪洋 虞林嫣 卞雨辰 安思瀚 杨博 向建军 杜关祥 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期409-415,共7页
An integrated quantum probe for magnetic field imaging is proposed,where the nitrogen–vacancy(NV)center fixed at the fiber tip is located on the periphery of flexible ring resonator.Using flexible polyimide(PI)as the... An integrated quantum probe for magnetic field imaging is proposed,where the nitrogen–vacancy(NV)center fixed at the fiber tip is located on the periphery of flexible ring resonator.Using flexible polyimide(PI)as the substrate medium,we design a circular microstrip antenna,which can achieve a bandwidth of 140 MHz at Zeeman splitting frequency of 2.87 GHz,specifically suitable for NV center experiments.Subsequently,this antenna is seamlessly fixed at a three-dimensional-printed cylindrical support,allowing the optical fiber tip to extend out of a dedicated aperture.To mitigate errors originating from processing,precise tuning within a narrow range can be achieved by adjusting the conformal amplitude.Finally,we image the microwave magnetic field around the integrated probe with high resolution,and determine the suitable area for placing the fiber tip(SAP). 展开更多
关键词 nitrogen-vacancy center conformal antenna integrated probe magnetic field imaging
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Assessment of Satisfaction in the Reception and Emergency Department of a Health Center
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作者 Boubacar Gueye Martial Coly Bop +6 位作者 NdéyeMarième Diagne Cheikh Tacko Diop Alioune Badara Tall Papa Gallo Sow Mountaga Dia Abdoul Aziz Ndiaye Ousseynou Ka 《Open Journal of Epidemiology》 2024年第2期284-296,共13页
Introduction The main objective of any healthcare establishment must be to ensure the quality of patient care and customer satisfaction. It is necessary to regularly assess patient satisfaction. The aim of this study ... Introduction The main objective of any healthcare establishment must be to ensure the quality of patient care and customer satisfaction. It is necessary to regularly assess patient satisfaction. The aim of this study was to assess the level of satisfaction of customers aged over 18 years attending the emergency department of the health center. Methodology This was a descriptive and analytical cross-sectional study of patients aged 18 years and over, who attended the Samu Municipal emergency department between 02 and 30 May 2023. The satisfaction index was determined using the adapted 2009 SAPHORA-MCO questionnaire and the Likert satisfaction scale. Results A total of 400 patients were surveyed. The average age was 35 years, with a standard deviation of 14.7. Of those surveyed, 51% were women, 87% were educated, 50% lived in Grand Yoff and 59.5% were unemployed. Satisfaction levels linked to perception of the cost of care (72%), waiting time (64.3%), information given to patients (69.1%) and pain management (74 .5%) are fair. On the other hand, the levels of satisfaction linked to administrative procedures (82.5%), staff attitudes towards patients (84%), staff availability (86.4%), patient privacy (89.2%), general atmosphere (87.2%), staff competence (87.3%), and the effectiveness of care (89.4%) were satisfactory. The average waiting time was 38 minutes. However, 32% of patients waited less than 30 minutes and 92% less than an hour. The satisfaction index linked to administration and reception was 72.9% and 79.85%, respectively. The satisfaction index linked to the administration and technical quality of care is equal to 85.8% and 83.7%, respectively. The overall satisfaction index is equal to 80.6%;the level of satisfaction of users of the health structure is satisfactory. Conclusion Patient satisfaction is an essential part of quality care. Patient satisfaction must be based on effective communication from the healthcare team and the creation of a patient-caregiver relationship. 展开更多
关键词 ASSESSMENT SATISFACTION Reception Ad Emergency Department Health center
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Why the abnormal phenomena of D-band center theory exist?A new BASED theory for surface catalysis and chemistry
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作者 Zelong Qiao Run Jiang +1 位作者 Jimmy Yun Dapeng Cao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期44-53,共10页
Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with th... Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces. 展开更多
关键词 Surface chemistry Surface catalysis D-band center theory Bonding orbital Anti-bonding orbital
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AMAD:Adaptive Mapping Approach for Datacenter Networks,an Energy-Friend Resource Allocation Framework via Repeated Leader Follower Game
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作者 Ahmad Nahar Quttoum Muteb Alshammari 《Computers, Materials & Continua》 SCIE EI 2024年第9期4577-4601,共25页
Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict th... Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict their utility objectives.Yet,besides the cost of the physical assets and network resources,such scaling may also imposemore loads on the electricity power grids to feed the added nodes with the required energy to run and cool,which comes with extra costs too.Thus,those CDNproviders who utilize their resources better can certainly afford their services at lower price-units when compared to others who simply choose the scaling solutions.Resource utilization is a quite challenging process;indeed,clients of CDNs usually tend to exaggerate their true resource requirements when they lease their resources.Service providers are committed to their clients with Service Level Agreements(SLAs).Therefore,any amendment to the resource allocations needs to be approved by the clients first.In this work,we propose deploying a Stackelberg leadership framework to formulate a negotiation game between the cloud service providers and their client tenants.Through this,the providers seek to retrieve those leased unused resources from their clients.Cooperation is not expected from the clients,and they may ask high price units to return their extra resources to the provider’s premises.Hence,to motivate cooperation in such a non-cooperative game,as an extension to theVickery auctions,we developed an incentive-compatible pricingmodel for the returned resources.Moreover,we also proposed building a behavior belief function that shapes the way of negotiation and compensation for each client.Compared to other benchmark models,the assessment results showthat our proposed models provide for timely negotiation schemes,allowing for better resource utilization rates,higher utilities,and grid-friend CDNs. 展开更多
关键词 Data center networks energy-aware resource management resource utilization game-theory mechanisms
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