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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 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.
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   
5.
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   
6.
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   
7.
Multidoped (Zn,Ti) gallium orthoferrite [GaFeO3 and Ga0.98Zn0.02Fe0.98Ti0.02O3] ceramic was synthesized through a solid-state reaction. X-ray analysis of the prepared material provides its basic crystal data of a single-phase orthorhombic system. The scattered crystallite size and lattice strain of the material were estimated. Analysis of the micrograph of field emission scanning electron microscope shows uniform grain distribution in the sample, suggesting the formation of good quality of sample. Founded on the magnetic measurements, it is concluded that (Zn,Ti)-modified gallium ferrite has provided a reduction in the Curie temperature (TC); however, no significant changes in the magnetization values with Zn and Ti integration in GaFeO3 lattice. A noteworthy effect of substitution of multiple elements at the Ga and Fe sites on dielectric constant and tangent loss of GaFeO3 has been observed. Complete studies of temperature (180–400 K) and frequency (10–107 Hz) dependence of dielectric constant and impedance have provided the effect of grains and grain boundaries on the conduction mechanism and dielectric relaxation of the material.  相似文献   
8.
This work describes the chemical doping effect on the magnetic properties of p-type transparent semiconductor with delafossitetype oxides CuCr 0.95 M 0.05 O 2 (M = Ni, Cr, Ga, V, Fe, Mn, and Zn). The lattice parameters were found to vary according to Vegard’s law. Reflection broadening is observed, that is ascribed to local lattice distortion due to the ionic radius difference between Cr 3+ and M dopants Raman spectra at a room temperature of CuCr 0.95 M 0.05 O 2 displayed three intense modes which are identified as σ(A 1g) at 691 cm ?1, σ(E g) at 444 cm ?1 and σ(A g) at 207 cm ?1 that matched with other delafossite structures. Magnetic susceptibility measurements show that the dominant interactions are antiferromagnetic (AFM) but that doping induces significant changes. A large ferromagnetic component arises in the Fe, V and Mn-substituted samples below ≈120 K. The Ni, Zn and Ga-substituted phases retain antiferromagnetic ordering at T N≈ 24 K. The main origin of the stabilization of the AFM state is probably the randomness induced by doping. The coupling between the local spins at the Cr sites and doped metal transition may enhance spin fluctuations at the Cr sites, which break the residual magnetic degeneracy as fluctuation-induced symmetry breaking in a highly magnetic degenerate groundstate manifold of some frustrated systems.  相似文献   
9.
10.
The CuCr1−xRhxO2 series is investigated by X-ray diffraction, magnetization measurements and Raman spectroscopy on ceramic samples. It is found that a delafossite solid solution is maintained up to x = 0.2 in CuCr1−xRhxO2. The small observed variation in cell parameters is consistent with the small difference between the ionic radii of Cr3+ and Rh3+. A significant broadening of X-ray reflections is observed and when analyzed using the Williamson-Hall relationship showed that the strain generated by Rh substitution is strongly anisotropic, affecting mainly (Cr,Rh)-O bonds in the ab plane. Room temperature Raman spectra displayed three main Raman active modes. All modes shift to lower frequency and undergo significant changes in intensity with increasing Rh content, showing the effect of Rh atoms on the M3+-O bond strength. The magnetic behavior of CuCr1−xRhxO2 samples was investigated as a function of temperature and applied field. At high temperature paramagnetic behavior, and at low temperature, evidence for weak ferromagnetism, reinforced by a hysteresis loop at 4 K is observed. The magnetic behavior of CuCr1−xRhxO2 is attributed to the disorder of Cr and Rh in octahedral sites resulting in short-range Cr-O-Cr and Cr-O-Rh interactions, which give rise to short-range weak ferromagnetism.  相似文献   
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