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Perspectives on non-emergent neonatal intensive care unit to pediatric intensive care unit care transfers in the United States
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作者 Phillip D Cohen Renee D Boss +3 位作者 David C Stockwell Meghan Bernier Joseph M Collaco Sapna R Kudchadkar 《World Journal of Critical Care Medicine》 2024年第4期73-80,共8页
BACKGROUND There is a substantial population of long-stay patients who non-emergently transfer directly from the neonatal intensive care unit(NICU)to the pediatric intensive care unit(PICU)without an interim discharge... BACKGROUND There is a substantial population of long-stay patients who non-emergently transfer directly from the neonatal intensive care unit(NICU)to the pediatric intensive care unit(PICU)without an interim discharge home.These infants are often medically complex and have higher mortality relative to NICU or PICUonly admissions.Given an absence of data surrounding practice patterns for nonemergent NICU to PICU transfers,we hypothesized that we would encounter a broad spectrum of current practices and a high proportion of dissatisfaction with current processes.AIM To characterize non-emergent NICU to PICU transfer practices across the United States and query PICU providers’evaluations of their effectiveness.METHODS A cross-sectional survey was drafted,piloted,and sent to one physician representative from each of 115 PICUs across the United States based on membership in the PARK-PICU research consortium and membership in the Children’s Hospital Association.The survey was administered via internet(REDCap).Analysis was performed using STATA,primarily consisting of descriptive statistics,though logistic regressions were run examining the relationship between specific transfer steps,hospital characteristics,and effectiveness of transfer.RESULTS One PICU attending from each of 81 institutions in the United States completed the survey(overall 70%response rate).Over half(52%)indicated their hospital transfers patients without using set clinical criteria,and only 33%indicated that their hospital has a standardized protocol to facilitate non-emergent transfer.Fewer than half of respondents reported that their institution’s nonemergent NICU to PICU transfer practices were effective for clinicians(47%)or patient families(38%).Respondents evaluated their centers’transfers as less effective when they lacked any transfer criteria(P=0.027)or set transfer protocols(P=0.007).Respondents overwhelmingly agreed that having set clinical criteria and standardized protocols for non-emergent transfer were important to the patient-family experience and patient safety.CONCLUSION Most hospitals lacked any clinical criteria or protocols for non-emergent NICU to PICU transfers.More positive perceptions of transfer effectiveness were found among those with set criteria and/or transfer protocols. 展开更多
关键词 TRANSFER Chronic critical illness Intensive care units Pediatric intensive care Neonatal intensive care Care transition
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Intermolecular Vibrational Energy Transfers in Melts and Solutions
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作者 沈宇能 蒋博 +5 位作者 葛传琦 邓罡华 陈海龙 杨学明 袁开军 郑俊荣 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期407-417,I0001,共12页
Resonant and nonresonant intermolecular vibrational energy transfers in Gdm- SCN/KSCN=1/1, GdmSCN/KS^13CN=1/1 and GdmSCN/KS^13C^15N=1/1 mixed crystals in melts and in aqueous solutions are studied with the two dimensi... Resonant and nonresonant intermolecular vibrational energy transfers in Gdm- SCN/KSCN=1/1, GdmSCN/KS^13CN=1/1 and GdmSCN/KS^13C^15N=1/1 mixed crystals in melts and in aqueous solutions are studied with the two dimensional infrared spectroscopy. The energy transfers in the samples are slower with a larger energy donor/acceptor gap, independent of the Raman spectra. The energy gap dependences of the nonresonant energy transfers cannot be described by the phonon compensation mechanism. Instead, the experi- mental energy gap dependences can be quantitatively described by the dephasing mechanism. Temperature dependences of resonant and nonresonant energy transfer rates in the melts are also consistent with the prediction of the dephasing mechanism. The series of results suggest that the dephasing mechanism can be dominant not only in solutions, but also in melts (pure liquids without solvents), only if the molecular motions (translations and rotations) are much faster than the nonresonant energy transfer processes. 展开更多
关键词 Vibrational energy transfers 2D IR Phonon compensation mechanism Dephasing mechanism
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Sperm DNA fragmentation does not affect the clinical outcomes in the cumulative transfers of an ICSI cycle along with blastocyst transfers in couples with normozoospermic male patients 被引量:1
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作者 Deepthi Repalle Saritha K.V. Shilpa Bhandari 《Asian pacific Journal of Reproduction》 2022年第3期125-131,共7页
Objective:To know whether sperm DNA fragmentation(SDF)affects the clinical outcomes in the cumulative transfers of an intracytoplasmic sperm injection(ICSI)cycle along with blastocyst transfers in couples with normozo... Objective:To know whether sperm DNA fragmentation(SDF)affects the clinical outcomes in the cumulative transfers of an intracytoplasmic sperm injection(ICSI)cycle along with blastocyst transfers in couples with normozoospermic males.Methods:The study included 252 couples who underwent their first ICSI cycles along with blastocyst transfer and whose male partner semen samples were normozoospermic according to the World Health Organization 2010 criteria.All the couples were classified into two groups based on the SDF:the low SDF group(SDF≤30%,n=162)and the high SDF group(SDF>30%,n=90).Clinical as well as laboratory outcomes were correlated between the two groups.Sperm DNA fragmentation was assessed on the post-wash semen samples by acridine orange test.The main outcome measures were the live birth rate and miscarriage rate.Results:A significant decrease in the live birth rates was observed in the high SDF group compared to the low SDF group in fresh embryo transfer cycles(P<0.05).However,no significant difference was observed in the clinical outcomes either in the frozen embryo transfer cycles or in the overall cumulative transfer cycles(P>0.05).No significant difference was observed in the laboratory outcomes between the two SDF groups.A remarkable decrease in sperm motility was observed in the high SDF group compared to the low SDF group(P<0.05).Conclusions:Sperm DNA fragmentation does not affect the clinical outcomes in the cumulative transfers of an ICSI cycle along with blastocyst transfers in couples with normozoospermic males. 展开更多
关键词 Sperm DNA fragmentation Intracytoplasmic sperm injection ICSI Live birth rates Blastocyst transfer Cumulative transfers
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Inter-hospital transfers and door-to-balloon times for STEMI: a single centre cohort study 被引量:1
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作者 RenéForsyth Zhong-Hua SUN +1 位作者 Christopher Reid Rachael Moorin 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第6期321-329,共9页
Background Key performance indices such as door-to-balloon times have long been recognized as quality metrics in reducing time to care for patients with acute coronary syndromes(ACS). In the situation where patients d... Background Key performance indices such as door-to-balloon times have long been recognized as quality metrics in reducing time to care for patients with acute coronary syndromes(ACS). In the situation where patients do not present to a facility capable of 24/7 percutaneous coronary interventions(PCI) delays in time to therapy can exceed the recommendation of 90 min or less. This study aimed to evaluate the impact of transfers on performance indices for patients diagnosed with ST-segment elevation myocardial infarction(STEMI). Methods Over a seven month collection period, all patients presenting with symptoms suggestive of ACS and admitted for PCI were studied. Patients were divided into dichotomous groups of direct presentations or transfers from a secondary non-PCI capable hospital with key times recorded, including symptom-onset, first hospital and PCI-capable hospital arrival and balloon inflation times to evaluate time of treatment for STEMI patients. Results Of the 87 patients diagnosed with STEMI, transferred patients experienced statistically significant delays in symptom-onset to the PCI-capable hospital(PCI-H) arrival(215 vs. 95 min, P < 0.001), symptom-onset to balloon inflation(225 vs. 160 min, P = 0.009) and first hospital arrival to balloon inflation times(106 vs. 56 min, P < 0.001). Only 28%(n = 9) of transferred patients underwent balloon inflation within 90 min from first hospital arrival, while 60%(n = 19) did within 120 min, although all received balloon inflation within 90 min from arrival at the PCI-H. After controlling for confounding factors of socio-economic status, presentation date/time and diagnostic category, transferred patients experienced an average 162% longer delays from symptom-onset to PCI-H door arrival, and 98% longer delays in symptom-onset to balloon inflation;compared to patients who present directly to the PCI-H. No statistically significant differences were noted between transferred and direct patients when measured from PCI-H door-to-balloon times. Conclusions This study shows that transferred patients experience a greater overall system delay, compared to patients who present directly for PCI, significantly increasing their time to treatment and therefore infarct times. Despite the majority of transfers experiencing pre-hospital activation, their treatment hospital arrival to balloon times are no less than direct presenters after controlling for confounding factors, further compounding the overall delay to therapy. 展开更多
关键词 Acute coronary syndrome Door-to-balloon times Inter-hospital transfers ST-segment elevation myocardial infarction
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Modeling and Numerical Simulation of Heat Transfers in a Metallic Pressure Cooker Isolated with Kapok Wool 被引量:1
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作者 Drissa Ouedraogo Serge Wendsida Igo +3 位作者 Gael Lassina Sawadogo Abdoulaye Compaore Belkacem Zeghmati Xavier Chesneau 《Modeling and Numerical Simulation of Material Science》 2020年第2期15-30,共16页
In this work, a numerical study of heat transfers in a metallic pressure cooker isolated with kapok wool was carried out. This equipment works like a thermos, allowing finishing cooking meals only thanks to the heat s... In this work, a numerical study of heat transfers in a metallic pressure cooker isolated with kapok wool was carried out. This equipment works like a thermos, allowing finishing cooking meals only thanks to the heat stored at the beginning of cooking, which generates energy savings. Cooked meals are also kept hot for long hours. In our previous work, we have highlighted the performances of the pressure cooker when making common dishes in Burkina Faso. Also, the parameters (thickness and density) of the insulating matrix allowing having such performances as well as the influence of the climatic conditions on the pressure cooker operation were analyzed in detail in this present work. The numerical methodology is based on the nodal method and the transfer equations obtained by making an energy balance on each node have been discretized using an implicit scheme with finite differences and resolved by the Gauss algorithm. Numerical results validated experimentally show that the thickness of the kapok wool as well as its density play an important role in the pressure cooker operation. In addition, equipment performances are very little influenced by the weather conditions of the city of Ouagadougou (Burkina Faso). 展开更多
关键词 Pressure Cooker Kapok Wool Heat transfers MODELING Nodal Method
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Effect of a High Silver Stress on the Element Transfers from a Smectite-Type Clay Substrate to Plants
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作者 Khadija Semhi Norbert Clauer +2 位作者 Sam Chaudhuri René Boutin Mohamed Hassan 《Green and Sustainable Chemistry》 2012年第2期76-89,共14页
Two species of radishes, Raphanus sativus and Raphanus raphanistrum, were grown in the laboratory in the same substrate consisting of a smectite-type clay, which was watered at the beginning of the experience with 50 ... Two species of radishes, Raphanus sativus and Raphanus raphanistrum, were grown in the laboratory in the same substrate consisting of a smectite-type clay, which was watered at the beginning of the experience with 50 ml of a solution containing either none or 1000, 2000 or 4000 mg/L of AgNO3, respectively. Occurrence of the toxic metal in the substrate outlines higher element uptakes by the cultivated species Raphanus sativus than by the wild species Raphanus raphanistrum, except for the highest degree of Ag pollution. After a one-month growth in the Ag-polluted substrate, Raphanus sativus was depleted in most of the major, trace and rare-earth elements, except for Al, Fe, Th, Ag and U that increased in the radishes from substrate polluted by 2000 mg/L of AgNO3, and Sr, Co, Ni, U and Ag that increased in the radishes from substrate polluted by 4000 mg/L of AgNO3. Raphanus raphanistrum was enriched in all elements except Si, Na, Rb and K in the polluted substrate. The uptake was monitored by a cation-exchange process in the rhy-zosphere between mineral particles and the watering solution in the presence of various enzymes with specific activities that induced a variable uptake with the REEs being even fractionated. These activities most probably depend on combined factors, such as the plant species, and the chemical and physical properties of the substrate. The results obtained here reveal also that accumulation of nutrient elements and others in the plants is not uniform at a given Ag pollution of the substrate and therefore at a given Ag contamination in the same plant species. 展开更多
关键词 Ag Pollution PLANT-GROWTH Experiment Smectite-Type CLAY SUBSTRATE SOIL-PLANT Element transfers REE Fractionation
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Deep Transfers of p-Class Tower Groups
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作者 Daniel C. Mayer 《Journal of Applied Mathematics and Physics》 2018年第1期36-50,共15页
Let p be a prime. For any finite p-group G, the deep transfers T H,G ' : H / H ' → G ' / G " from the maximal subgroups H of index (G:H) = p in G to the derived subgroup G ' are introduced as an ... Let p be a prime. For any finite p-group G, the deep transfers T H,G ' : H / H ' → G ' / G " from the maximal subgroups H of index (G:H) = p in G to the derived subgroup G ' are introduced as an innovative tool for identifying G uniquely by means of the family of kernels ùd(G) =(ker(T H,G ')) (G: H) = p. For all finite 3-groups G of coclass cc(G) = 1, the family ùd(G) is determined explicitly. The results are applied to the Galois groups G =Gal(F3 (∞)/ F) of the Hilbert 3-class towers of all real quadratic fields F = Q(√d) with fundamental discriminants d > 1, 3-class group Cl3(F) □ C3 × C3, and total 3-principalization in each of their four unramified cyclic cubic extensions E/F. A systematic statistical evaluation is given for the complete range 1 d 7, and a few exceptional cases are pointed out for 1 d 8. 展开更多
关键词 Hilbert p-Class Field Towers p-Class GROUPS p-Principalization Quadratic FIELDS Dihedral FIELDS of Degree 2p Finite p-Groups Two-Step Centralizers Polarization PRINCIPLE Descendant Trees p-Group Generation Algorithm p-Multiplicator RANK Relation RANK Generator RANK Deep transfers Shallow transfers Partial Order and Monotony PRINCIPLE of Artin Patterns Parametrized Polycyclic pc-Presentations Commutator Calculus
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Agricultural Machinery Input,Labor Resource Allocation,and Rural Household Land Transfers
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作者 Zhao Lei Liu Li 《Contemporary Social Sciences》 2022年第6期1-18,共18页
This paper explores the impact of agricultural machinery input on rural households’land transfers,which is conducive to the acceleration of agricultural modernization,agricultural production at scale,and rural revita... This paper explores the impact of agricultural machinery input on rural households’land transfers,which is conducive to the acceleration of agricultural modernization,agricultural production at scale,and rural revitalization.By using the micro-data on rural households(2014–2018)from China Family Panel Studies(CFPS),we made an empirical analysis of the impact of agricultural machinery input on land transfers and drew three conclusions.First,agricultural machinery input has a positive impact on land transfers,which means the more rural households invest in agricultural machinery,the more willing they are to participate in land transfers.Second,the impact of agricultural machinery input on land transfers is mainly exerted by adjusting the allocation of labor resources for rural households,or rather by increasing the number of farmers engaged in agriculture and reducing the number of farmers-turned traders and workers to facilitate land transfers.Third,the impact of agricultural machinery input on land transfers concerns both the positive transfers-in and the negative transfers-out,and such an impact stays stable across income groups.Accordingly,we should further increase agricultural machinery-related subsidies,improve the agricultural machinery service outsourcing market,and help rural households to reasonably allocate their labor resource endowments and invest in agricultural machinery to increase land transfers. 展开更多
关键词 agricultural machinery input CMP model land transfers labor resource allocation
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Two Great Transfers of Word Emotive Overtones In Modern Chinese
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作者 Diao Yanbin Ye Jiaquan 《宏观语言学》 2008年第1期89-104,共16页
Since 1949, modern Chinese language has, in the course o f its development in China's Mainland, twice witnessed large-scale transfers in its word emotive overtones. The first began in 1949 and went on all the way ... Since 1949, modern Chinese language has, in the course o f its development in China's Mainland, twice witnessed large-scale transfers in its word emotive overtones. The first began in 1949 and went on all the way till the end o f the Cultural Revolution in 1977. Derogation manifested itself in that period, during which the derogatory words enjoyed their greatest number, widest usages and highest frequency in the history o f the Chinese language. The second began from the Reform and Opening Up Policy in 1978 and lasted untill now. De-derogation has manifested itself in this period, during which the derogatory words have had the smallest number, least usages and lowest frequency in the history o f the Chinese language. The two large-scale transfers result from their specific social backgrounds and the development o f the Chinese language itself. 展开更多
关键词 MODERN CHINESE LANGUAGE emotive OVERTONES transfers
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Time Optimization of Multiple Knowledge Transfers in the Big Data Environment 被引量:3
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作者 Chuanrong Wu Evgeniya Zapevalova +1 位作者 Yingwu Chen Feng Li 《Computers, Materials & Continua》 SCIE EI 2018年第3期269-285,共17页
In the big data environment, enterprises must constantly assimilate big dataknowledge and private knowledge by multiple knowledge transfers to maintain theircompetitive advantage. The optimal time of knowledge transfe... In the big data environment, enterprises must constantly assimilate big dataknowledge and private knowledge by multiple knowledge transfers to maintain theircompetitive advantage. The optimal time of knowledge transfer is one of the mostimportant aspects to improve knowledge transfer efficiency. Based on the analysis of thecomplex characteristics of knowledge transfer in the big data environment, multipleknowledge transfers can be divided into two categories. One is the simultaneous transferof various types of knowledge, and the other one is multiple knowledge transfers atdifferent time points. Taking into consideration the influential factors, such as theknowledge type, knowledge structure, knowledge absorptive capacity, knowledge updaterate, discount rate, market share, profit contributions of each type of knowledge, transfercosts, product life cycle and so on, time optimization models of multiple knowledgetransfers in the big data environment are presented by maximizing the total discountedexpected profits (DEPs) of an enterprise. Some simulation experiments have beenperformed to verify the validity of the models, and the models can help enterprisesdetermine the optimal time of multiple knowledge transfer in the big data environment. 展开更多
关键词 Big data knowledge transfer time optimization DEP simulation experiment
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Influence of Blastocysts Morphological Score on Pregnancy Outcomes in Frozen-thawed Blastocyst Transfers: a Retrospective Study of 741 Cycles 被引量:2
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作者 刘琳 李艳辉 +3 位作者 丁晓芳 耿育红 陈春艳 高颖 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第5期750-754,共5页
The influence of inner cell mass (ICM) and trophectoderm (TE) score on pregnancy out- comes in frozen-thawed blastocyst transfer cycles was analyzed. A retrospective analysis of 741 cycles of frozen-thawed blastos... The influence of inner cell mass (ICM) and trophectoderm (TE) score on pregnancy out- comes in frozen-thawed blastocyst transfer cycles was analyzed. A retrospective analysis of 741 cycles of frozen-thawed blastosysts transfer was performed. All cycles were divided into four groups based on the number and morphological score of blastocysts: S-ICM B/TE B group (n=91), the single blastocyst transfer oflCM B and TE B; D-ICM B/TE B group (n=579), double blastocysts transfer oflCM B/TE B; D-1CM B/TE C group (n=35), double blastocysts transfer of ICM B/TE C; and D-ICM C/TE B group (n=36), double blastocysts transfer ofTE B/ICM C. The pregnancy outcomes were compared among the four groups. As compared with D-ICM B/TE C group, the clinical pregnancy rate, implantation rate and multiple pregnancy rate were increased in D-ICM B/TE B group (74.96% vs. 57.14%, 57.43% vs. 37.14%, and .48.62% vs. 25%, respectively, P〈0.05 for all). Clinical pregnancy rate and implantation rate in D-ICM B/TE B group were also higher than in D-ICM C/TE B group (74.96% vs. 50%, and 57.43% vs. 33.33%, both P〈0.05). Multivariable Logistic regression analysis indicated that ICM score was a better predictive parameter for clinical pregnancy (OR=3.05, CI 1.70-5.46, P〈0.001), while the trophectoderm score was a better one for early abortion (OR=0.074, CI 0.03-0.19, P〈0.001). Clinical pregnancy rate and multiple pregnancy rate in S-ICM B/TE B group were significantly lower than those in D-ICM B/TE B group (46.15% vs. 74.96%, and 2.38% vs. 48.62%, both P〈0.05), but there was no si~,,niflcant difference in the implantation rate between the two groups. It was suggested that the higher score of ICM and TE may be indicative of the better pregnancy outcomes. The ICM score is a better predictor of clinical pregnancy than TE, while TE score is a better one in predicting early abortion. Sin- gle ICM B/TE B blastocyst transfer in frozen-thawed cycles can also get satisfactory pregnancy out- comes. 展开更多
关键词 thawed embryos transfer vitrification cryopreservation inner cell mass trophectoderm cell pregnancy outcome
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Towards electrochemical hydrogen storage in liquid organic hydrogen carriers via proton-coupled electron transfers 被引量:1
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作者 Hamid Ghorbani Shiraz Mikhail Vagin +7 位作者 Tero-Petri Ruoko Viktor Gueskine Krzysztof Karon Mieczystaw tapkowski Tobias Abrahamsson Thomas Ederth Magnus Berggren Xavier Crispin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期292-300,I0007,共10页
Green hydrogen is identified as one of the prime clean energy carriers due to its high energy density and a zero emission of CO_(2).A possible solution for the transport of H_(2)in a safe and low-cost way is in the fo... Green hydrogen is identified as one of the prime clean energy carriers due to its high energy density and a zero emission of CO_(2).A possible solution for the transport of H_(2)in a safe and low-cost way is in the form of liquid organic hydrogen carriers(LOHCs).As an alternative to loading LOHC with H_(2)via a two-step procedure involving preliminary electrolytic production of H_(2)and subsequent chemical hydrogenation of the LOHC,we explore here the possibility of electrochemical hydrogen storage(EHS)via conversion of proton of a proton donor into a hydrogen atom involved in covalent bonds with the LOHC(R)via a protoncoupled electron transfer(PCET)reaction:2nH^(+)+2ne^(-)+Rox■n H_(2)^(0)Rred.We chose 9-fluorenone/fluorenol(Fnone/Fnol)conversion as such a model PCET reaction.The electrochemical activation of Fnone via two sequential electron transfers was monitored with in-situ and operando spectroscopies in absence and in presence of different alcohols as proton donors of different reactivity,which enabled us to both quantify and get the mechanistic insight on PCET.The possibility of hydrogen extraction from the loaded carrier molecule was illustrated by chemical activation. 展开更多
关键词 Proton-coupled electron transfer Electrochemical hydrogen storage Hydrogen bonding agent Anion-radical Comproportionation
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Consideration of Size and Dimension in the Evaluation of Transfers during Convective Drying of Sweet Potato 被引量:1
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作者 Abdou-Salam Ganame Kondia Honore Ouoba François Zougmore 《Journal of Analytical Sciences, Methods and Instrumentation》 2020年第4期104-112,共9页
This work is interested in solving the complex problem of understanding mass transfers in biological media. The contribution of the initial sample size is taken into account. Transfers are established more efficiently... This work is interested in solving the complex problem of understanding mass transfers in biological media. The contribution of the initial sample size is taken into account. Transfers are established more efficiently in small samples. Thus, from the first 50 minutes, the cubic sample at 1 cm stop is already at 50% while the sample at 4 cm edge is at about 90% of its initial water content. Likewise the shape is combined with the size. But it is revealed that if we fix similar characteristic dimensions, we can bypass the notion of initial shape. Thus the cubic samples 4 cm of edges. 4 cm diameter of spherical shape, 4 cm × 4 cm height-diameter cylindrical one, all dry identically. 展开更多
关键词 Mass Transfer SIZE SHAPE Agri-Food Products
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NUMERICAL SIMULATION OF HEAT,MASS AND MOMENTUM TRANSFERS IN METALLIC INGOTS AND PREDICTION OF MACROSEGREGATION
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第7期37-41,共5页
A continuum model and numerical methods were established for description of heat,mass and momentum transfers as well as macrosegregation formations in metallic ingots.Numerical simulation of temperature,composition an... A continuum model and numerical methods were established for description of heat,mass and momentum transfers as well as macrosegregation formations in metallic ingots.Numerical simulation of temperature,composition and liquid flow fields during the solidification of an Al-4.5% Cu ingot were performed on an IBM personal computer.The model and numerical methods were verified through two experiments. 展开更多
关键词 numerical simulation heat transfer mass transfer momentum transfer Al-Cu alloy MACROSEGREGATION
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Multiple Energy Transfers in Rare Earth Complex-Doped SiO_2 Spheres
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作者 黄昌清 孙婷 +1 位作者 田维坚 赵保平 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第2期134-137,共4页
Silica spheres doped with Eu (TTFA)3 and/or Sm(TTFA)3 were synthesized by using the modified Stober method. The transmission electron microscope image reveals that the hybrid spheres have smooth surfaces and an av... Silica spheres doped with Eu (TTFA)3 and/or Sm(TTFA)3 were synthesized by using the modified Stober method. The transmission electron microscope image reveals that the hybrid spheres have smooth surfaces and an average diameter of about 210 nm. Fluorescence spectrometer was used to analyze the fluorescence properties of hybrid spheres. The results show that multiple energy transfer processes are simultaneously achieved in the same samples co-doped with Eu (TTFA)3 and Sm(TTFA)3, namely between the ligand and Eu^3+ ion, the ligand and Sm^3+ ion, and Sm^3+ ion and Eu^3+ ion. Energy transfer of Sm^3+→Eu^3+ in the hybrid spheres leads to fluorescence enhancement of Eu^3+ emission by approximately an order of magnitude. The lifetimes of the hybrid spheres were also measured. 展开更多
关键词 OPTICS silica hybrid spheres CO-DOPED rare earth complex SENSITIZATION energy transfer
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A Review of the Eco-Environmental Impacts of the South-to-North Water Diversion:Implications for Interbasin Water Transfers
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作者 Hanlu Yan Yuqing Lin +6 位作者 Qiuwen Chen Jianyun Zhang Shufeng He Tao Feng Zhiyuan Wang Cheng Chen Jue Ding 《Engineering》 SCIE EI CAS CSCD 2023年第11期161-169,共9页
Interbasin water-transfer schemes provide an engineering solution for reconciling the conflict between water demand and availability.In the context of climate change,which brings great uncertainties to water resource ... Interbasin water-transfer schemes provide an engineering solution for reconciling the conflict between water demand and availability.In the context of climate change,which brings great uncertainties to water resource distribution,interbasin water transfer plays an increasingly important role in the global water–food–energy nexus.However,the transfer of water resources simultaneously changes the hydrological regime and the characteristics of local water bodies,affecting biotic communities accordingly.Compared with high economic and technical inputs water-transfer projects require,the environmental and ecological implications of water-transfer schemes have been inadequately addressed.This work selects the largest water-transfer project in China,the South-to-North Water Diversion(SNWD)Project,to critically review its eco-environmental impacts on donor and recipient basins,as well as on regions along the diversion route.The two operated routes of the SNWD Project represent two typical water diversion approaches:The Middle Route uses an excavated canal,while the East Route connects existent river channels.An overview of the eco-environmental implications of these two routes is valuable for the design and optimization of future water-transfer megaprojects. 展开更多
关键词 Interbasin water transfer Water resources ECOSYSTEM Water quality Environmental impacts
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High-fidelity topological quantum state transfers in a cavity-magnon system
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作者 包茜茜 郭刚峰 +1 位作者 杨煦 谭磊 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期150-155,共6页
We propose a scheme for realizing high-fidelity topological state transfer via the topological edge states in a onedimensional cavity-magnon system.It is found that the cavity-magnon system can be mapped analytically ... We propose a scheme for realizing high-fidelity topological state transfer via the topological edge states in a onedimensional cavity-magnon system.It is found that the cavity-magnon system can be mapped analytically into the generalized Su-Schrieffer-Heeger model with tunable cavity-magnon coupling.It is shown that the edge state can be served as a quantum channel to realize the photonic and magnonic state transfers by adjusting the coupling strength between adjacent cavity modes.Further,our scheme can realize the quantum state transfer between photonic state and magnonic state by changing the cavity-magnon coupling strength.With the numerical simulation,we quantitatively show that the photonic,magnonic and magnon-to-photon state transfers can be achieved with high fidelity in the cavity-magnon system.Spectacularly,three different types of quantum state transfer schemes can be even transformed into each other in a controllable fashion.The Su-Schrieffer-Heeger model based on the cavity-magnon system provides us a tunable platform to engineer the transport of photon and magnon,which may have potential applications in topological quantum processing. 展开更多
关键词 topological state transfer cavity-magnon system high fidelity
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Reconstruction of thumb together with the first metacarpus of 10 cases using the modified method of free transfers of second toe and composite tissue
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作者 褚晓朝 黄耀添 陆裕朴 《Journal of Medical Colleges of PLA(China)》 CAS 1994年第3期235-239,共5页
in the paper the results of reconstruction of thumb and first matacarpus of 10 cases are reported. All the 10 transplantations were successful and revealed fine recovery of function and appearance.It was considered th... in the paper the results of reconstruction of thumb and first matacarpus of 10 cases are reported. All the 10 transplantations were successful and revealed fine recovery of function and appearance.It was considered that the method of simultaneous removal of the second toe and metatarsus,first web space of the foot and the dorsal pedis flap for reconstruction of thumb and metacarpus to be superior to traditional methods in many aspects.Revascularization by anastomosis between the dorsalis pedis artery and the proximal end of the radial artery and that between the first plantar metatarsal artery and the distal end of the radial artery is effective to overcome ischemia of transplants because of variation of the first dorsal metatarsal artery. 展开更多
关键词 TOE transfer RECONSTRUCTION of THUMB dorsalis pedis FLAP
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Analyzing Service Rates for File Transfers in Peer-to-peer File Sharing Systems
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作者 王凯 潘理 李建华 《Journal of Donghua University(English Edition)》 EI CAS 2008年第6期700-705,共6页
When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing th... When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing the distribution of server-like nodes' upstream-bandwidth among their concurrent transfers. A sufficient condition for the service rate, what a receiver obtains for downloading a file, to asymptotically be uniform is presented. On the aggregate service rate for transferring a file in a system, a sufficient condition for it to asymptotically follow a Zipf distribution is presented. These asymptotic equalities are both in the mean square sense. These analyses and the sufficient conditions provide a mathematic base for modeling file transfer processes in peer-to-peer file sharing systems. 展开更多
关键词 PEER-TO-PEER file sharing system service rate file transfer Zipf distribution asymptotic equality
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Heat and Mass Transfers in a Two-Phase Stratified Turbulent Fluid Flow in a Geothermal Pipe with Chemical Reaction
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作者 Eric M. Nyariki Mathew N. Kinyanjui Jeconia O. Abonyo 《Journal of Applied Mathematics and Physics》 2023年第2期484-513,共30页
This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing... This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing the flow were solved using the Finite Difference Method. The effects of various physical parameters on the concentration, skin friction, heat, and mass transfers have been determined. Analysis of the results obtained indicated that the coefficient of skin friction decreased with an increase in Reynolds number and solutal Grasholf number, the rate of heat transfer increased with an increase in Eckert number, Prandtl number, and angle of inclination, and the rate of mass transfer increased with increase in Reynolds number, Chemical reaction parameter and angle of inclination. The findings would be useful to engineers in designing and maintaining geothermal pipelines more effectively. 展开更多
关键词 TWO-PHASE Turbulence Non-Newtonian INCLINATION Heat Transfer Mass Transfer STRATIFIED
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