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1.
The present paper deals with the extraction of some minerals (potassium, calcium and magnesium) from ground, dried aerial parts of white lady's bedstraw (Galium mollugo L.) using an aqueous ethanol solution (50% by volume) at different temperatures (from 23 to 40 °C) in the presence and absence of ultrasound. The main goal was to establish the kinetics and the thermodynamics of the two extraction processes. A phenomenological model involving simultaneous washing and diffusion was proved for both ultrasound-assisted and silent extraction of the minerals. The minerals extraction both in the presence and the absence of ultrasound is endothermic and irreversible since the enthalpy change and the entropy change are positive in the ranges of extraction temperature applied. The Gibbs free energy change for the extraction of minerals is negative, indicating that the process is feasible and spontaneous. The minerals yield increased by a factor of 1.02–1.06 and 1.14–1.27 in the absence and the presence of ultrasound, respectively for every 10 °C rise in temperature.  相似文献   
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Mucopolysaccharidoses (MPS’s) represent a subgroup of lysosomal storage diseases related to a deficiency of enzymes that catalyze glycosaminoglycans degradation. Mucopolysaccharidosis type I (MPS I) is a rare autosomal recessive disorder caused by a deficiency of α-l-iduronidase encoded by the IDUA gene. Partially degraded heparan sulfate and dermatan sulfate accumulate progressively and lead to multiorgan dysfunction and damage. The aim of this study is to describe the clinical, biochemical, and molecular characteristics of 13 Algerian patients from 11 distinct families. MPS I diagnosis was confirmed by molecular study of the patients’ IDUA gene. Clinical features at the diagnosis and during the follow-up are reported. Eighty-four percent of the studied patients presented with a mild clinical phenotype. Molecular study of the IDUA gene allowed the characterization of four pathological variations at the homozygous or compound heterozygote status: IDUA NM_00203.4:c.1598C>G-p.(Pro533Arg) in 21/26 alleles, IDUA NM_00203.4:c.532G>A-p.(Glu178Lys) in 2/26 alleles, IDUA NM_00203.4:c.501C>G-p.(Tyr167*) in 2/26 alleles, and IDUA NM_00203. 4: c.1743C>G-p.(Tyr581*) in 1/26 alleles. This molecular study unveils the predominance of p.(Pro533Arg) variation in our MPS I patients. In this series, the occurrence of some clinical features linked to the Scheie syndrome is consistent with the literature, such as systematic valvulopathies, corneal opacity, and umbilical hernia; however, storage signs, facial dysmorphic features, and hepatomegaly were more frequent in our series. Screening measures for these debilitating diseases in highly consanguineous at-risk populations must be considered a priority health problem.  相似文献   
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Our recent progress in the analysis and reconstruction of real porous media are surveyed and some emphasis is put on the two-field and on the grain reconstruction methods. Then, after a short summary of our previous analyses of transports, two recent developments are presented, namely, the determination of the resistivity index and of the dispersion tensor in multiphase flow.  相似文献   
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The use of primary cells in human liver therapy is limited by a lack of cells. Induced pluripotent stem cells (iPSCs) represent an alternative to primary cells as they are infinitely expandable and can be differentiated into different liver cell types. The aim of our work was to demonstrate that simian iPSCs (siPSCs) could be used as a new source of liver cells to be used as a large animal model for preclinical studies. We first differentiated siPSCs into a homogenous population of hepatoblasts (siHBs). We then separately differentiated them into hepatocytes (siHeps) and cholangiocytes (siChols) expressing respective specific markers and displaying epithelial polarity. Moreover, we showed that polarized siChols can self-organize into 3D structures. These results should facilitate the deciphering of liver development and open the way to exploring co-culture systems that could be assessed during preclinical studies, including in autologous monkey donors, for regenerative medicine purposes.  相似文献   
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We present a study of the effect of Ga-doping on the physical properties of La0.75Ca0.1Sr0.15Mn1?x Ga x O3 (x=0.025, 0.075 and 0.1) compounds prepared by the sol-gel method. The variation of the magnetization (M) vs. temperature (T), under an applied magnetic field of 0.05 T, reveals a ferromagnetic–paramagnetic transition for all samples. The magnetization behavior and the Curie temperature T C have shown a large dependence on the fractional composition x. In fact, the M(T) curves have revealed the presence of a long-range ferromagnetic state below T C. The magnetotransport properties have been investigated based on the temperature dependence of the resistivity ρ(T) measurements. We have noted that these samples present an electrical transition from a paramagnetic-semiconductor state to a ferromagnetic-metallic one, when decreasing temperature. We have used the phenomenological equation for conductivity under a percolation approach, which is based upon an approach that the system consists of the phase separated ferromagnetic metallic and paramagnetic insulating regions. We have then fitted the resistivity data measured in the range of 15–300 K and found that the activation barrier decreases with the raising Ga3+ ion concentration.  相似文献   
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Synthesis, crystal structure, vibrational study and magnetic properties of the compound (C7H18N2) CuCl4 are reported. The latter crystallizes in the monoclinic system (space group P2 1, Z = 4) with the following unit cell dimensions: a = 7.569(5) Å b = 14.174(5) Å, c = 13.193(2) Å and β = 105.53(3)°. Besides, its structure was solved using 5754 independent reflections down to R = 0.0475. The atomic arrangement can be described by alternating organic and inorganic layers stacked in the [\(\bar {1}\)01] direction, made up of tetrahedral of tetrachlorocuprate CuCl\(_{4}^{2-}\) sandwiched between two organic layers. In crystal structure, the inorganic layer, built up by independent monomeric [CuCl4]2?, is connected to the organic ones through hydrogen bonding in order to build a three-dimensional network. The magnetic behavior of (C7H18N2) CuCl4 samples was investigated as a function of temperature and applied field. At hightemperature paramagnetic behavior, and at low temperature, evidence for weak ferromagnetism, reinforced by a hysteresis loop at 2 K is observed. The magnetic behavior of (C7H18N2) CuCl4 is attributed to Cu (II) due to the presence of an active Jahn–Teller effect in the d 9 electronic system, which give rise to short-range weak ferromagnetism.  相似文献   
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