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1.
Single crystals of gadolinium–sodium polyphosphate NaGd(PO3)4 were grown for the first time using a flux method and characterized by X-ray diffraction. This phosphate crystallizes in a monoclinic system with P21/n space group and with the following unit-cell dimensions: a = 9.767(3) Å, b = 13.017(1) Å, c = 7.160(2) Å, β = 90.564(5)°, V = 910.3(4) Å3 and Z = 4. The crystal structure was solved from 3451 X-ray independent reflections with final R(F2) = 0.0219 and Rw(F2) = 0.056 refined with 164 parameters (). The atomic arrangement can be described as a long chain polyphosphate organization. Two infinite (PO3)∝ chains with a period of eight tetrahedra run along the [0 1 1] direction. The structure of NaGd(PO3)4 consists of GdO8 polyhedra sharing oxygen atoms with phosphoric group PO4. Each Na+ ion is bonded to eight oxygen atoms. 相似文献
2.
DRYING KINETICS AND CHARACTERISTIC DRYING CURVE OF LIGHTLY SALTED SARDINE (SARDINELLA AURITA) 总被引:5,自引:0,他引:5
Drying of lightly salted sardine (Sardinella aurita) was accomplished using three air temperatures (35°C, 40°C, 50°C) and three air velocities (0.5 m/s, 1.5 m/s, 2 m/s); the effects of drying conditions on drying kinetics were studied. As for all biological products, air temperature is the main factor influencing the drying kinetics. However, over a given temperature which seems to correspond to protein modification (50°C), and at a high air flow rate (2 m/s and 2.5 m/s) a crust formation on the surface of the fish, due to the combined effect of heat and salt was observed. This phenomenon inhibited the drying rate. From the drying curves, two falling rate periods were observed. The dimensionless drying rate versus a dimensionless moisture content data were regressed by the Marquardt Levenberg non-linear optimization method to obtain an empirical equation describing the salted sardine characteristic drying curve. 相似文献
3.
This article examines how web-based interorganizational information systems(ios)can efficiently support coordination mechanisms between outsourcer and third party logistics (3PL). First, we review the literature on coordination mechanisms andios. Second, we report on the methodology used for gathering information on outsourcers and 3PLs. Third, armed with limited but quality data, we identified two fundamental dimensions: 3PL involvement andios impacts on logistics outsourcing decisions. By combining the two dimensions, we propose a conceptual framework that highlights four main categories ofios that we characterize as neutralios, supply chainios, strategicios and dynamicios. After characterizing and analyzing each category, we discuss how these web basedios support outsourcers and 3PL along the supply chain. Finally, the article discusses the framework’s relevancy and its limits. 相似文献
4.
5.
The influence of pulsed electric field (PEF) and subsequent centrifugal osmotic dehydration (OD) on the convective drying behavior of carrot is investigated. The PEF was carried out at an intensity of E = 0.60 kV/cm and a treatment duration of tPEF = 50 ms. The following centrifugal OD was performed in a sucrose solution of 65% (w/w) at 40°C for 0, 1, 2, or 4 h under 2400 × g. The drying was performed after the centrifugal OD for temperatures 40-60°C and at constant air rate (6 m3/h).
With the increase of OD duration the air drying time is reduced spectacularly. The dimensionless moisture ratio Xr = 0.1 is reached for PEF-untreated carrots after 370 min of air drying at 60°C in absence of centrifugal OD against 90 min of air drying after the 240 min of centrifugal OD. The PEF treatment reduces additionally the air drying time. The total time of dehydration operations can be shortened when OD time is optimized. For instance, the minimal time required to dehydrate untreated carrots until Xr = 0.1 is 260 min (120 min of OD at 40°C and 140 min of drying at 60°C). It is reduced to 230 min with PEF-treated carrots.
The moisture effective diffusivity Deff is calculated for the convective air drying based on Fick's law. The centrifugal OD pretreatment increases drastically the value of Deff. For instance, 4 h of centrifugal OD permitted increasing the value of Deff from 0.93 · 10-9 to 3.85 · 10-9 m2/s for untreated carrots and from 1.17 · 10-9 to 5.10 · 10-9 m2/s for PEF-treated carrots. 相似文献
With the increase of OD duration the air drying time is reduced spectacularly. The dimensionless moisture ratio Xr = 0.1 is reached for PEF-untreated carrots after 370 min of air drying at 60°C in absence of centrifugal OD against 90 min of air drying after the 240 min of centrifugal OD. The PEF treatment reduces additionally the air drying time. The total time of dehydration operations can be shortened when OD time is optimized. For instance, the minimal time required to dehydrate untreated carrots until Xr = 0.1 is 260 min (120 min of OD at 40°C and 140 min of drying at 60°C). It is reduced to 230 min with PEF-treated carrots.
The moisture effective diffusivity Deff is calculated for the convective air drying based on Fick's law. The centrifugal OD pretreatment increases drastically the value of Deff. For instance, 4 h of centrifugal OD permitted increasing the value of Deff from 0.93 · 10-9 to 3.85 · 10-9 m2/s for untreated carrots and from 1.17 · 10-9 to 5.10 · 10-9 m2/s for PEF-treated carrots. 相似文献
6.
Itagaki M. Amami K. Tomura Y. Yuhaku S. Ishimaru Y. Bessho Y. Eda K. Ishida T. 《Advanced Packaging, IEEE Transactions on》1999,22(3):366-371
A new chip scale package (CSP) using an organic laminated substrate called μCSP was developed, which was fabricated using ALIVH substrate as a interposer and stud-bump-bonding (SBB) flip-chip technology. The ALIVH substrate is a multilayered organic substrate with inner via holes in any layer. The newly developed CSP-L using ALIVH substrate realized a miniaturization of its package size to the same as a CSP using a ceramic substrate (CSP-C). In order to perform the SBB flip-chip bonding onto the ALIVH substrate, an excellent coplanarity of the substrate surface was required. The required coplanarity was obtained using a fixture during the SBB flip-chip bonding process. The first-level packaging reliability and the second-level packaging reliability onto ALIVH mother board were evaluated. The resulting reliabilities were good enough to apply to practical use 相似文献
7.
Naceur Etteyeb Leila Dhouibi Mercedes Sanchez Cruz Alonso Carmen Andrade Ezzeddine Triki 《Journal of Materials Science》2007,42(13):4721-4730
The aim of this study is to investigate the viability of use of sodium phosphate (Na3PO4: SP), tetrasodium pyrophosphate (Na4P2O7: TSPP) and hydroxyethylidene-diphosphonic acid (C2H8O7P2: HEDP) as a non-toxic corrosion inhibitors of steel bars in alkaline media which simulate the electrolyte in the concrete
pores. The effectiveness of these phosphate compounds as corrosion inhibitors was investigated by measuring the corrosion
potentials, the polarization curves, the corrosion current densities, and the electrochemical impedance spectroscopy of steel
bars immersed for 30 days in saturated Ca(OH)2 solutions with and without chlorides. At the completion of the tests, the mass losses were determined in order to verify
the reliability of the electrochemical results. The results showed that phosphate compounds form a protective layer on the
steel surface when immersed in alkaline solution without chlorides. In the presence of chloride ions, the SP acts as an anodic
inhibitor and reduces the corrosion activity on steel. The HEDP shows lower efficiency, probably due to the decrease of the
pH and to the high [Cl−]/[inh] ratio used. Results obtained by electrochemical and gravimetric methods are in quite reasonable agreement. 相似文献
8.
Kerbiche Asma Jabra Saoussen Ben Zagrouba Ezzeddine Charvillat Vincent 《Multimedia Tools and Applications》2018,77(20):26769-26791
Multimedia Tools and Applications - Video watermarking technique aims at resolving insecurity problems. Recently, many approaches have been proposed in order to satisfy the new constraints of video... 相似文献
9.
A new debate on the potential impact of oil price changes on the value of firms was initiated in this paper. Using a stochastic frontier approach, an attempt was made to derive the optimal value Q* of firms and calculate the Q value observed. Then the shortfall (Q*–Q) which represents the inefficiency term was explained. Starting from 19 industrial Tunisian firms listed on the Tunis Stock Exchange between 2007 and 2011, the fact that variation of oil prices can largely explain distortions in the value of firms was empirically demonstrated. 相似文献
10.
The influence of pulsed electric field (PEF) and subsequent centrifugal osmotic dehydration (OD) on the convective drying behavior of carrot is investigated. The PEF was carried out at an intensity of E = 0.60 kV/cm and a treatment duration of t PEF = 50 ms. The following centrifugal OD was performed in a sucrose solution of 65% (w/w) at 40°C for 0, 1, 2, or 4 h under 2400 × g. The drying was performed after the centrifugal OD for temperatures 40–60°C and at constant air rate (6 m3/h). With the increase of OD duration the air drying time is reduced spectacularly. The dimensionless moisture ratio Xr = 0.1 is reached for PEF-untreated carrots after 370 min of air drying at 60°C in absence of centrifugal OD against 90 min of air drying after the 240 min of centrifugal OD. The PEF treatment reduces additionally the air drying time. The total time of dehydration operations can be shortened when OD time is optimized. For instance, the minimal time required to dehydrate untreated carrots until Xr = 0.1 is 260 min (120 min of OD at 40°C and 140 min of drying at 60°C). It is reduced to 230 min with PEF-treated carrots. The moisture effective diffusivity D eff is calculated for the convective air drying based on Fick's law. The centrifugal OD pretreatment increases drastically the value of D eff . For instance, 4 h of centrifugal OD permitted increasing the value of D eff from 0.93 · 10?9 to 3.85 · 10?9 m2/s for untreated carrots and from 1.17 · 10?9 to 5.10 · 10?9 m2/s for PEF-treated carrots. 相似文献