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991.
Electrical conductivity measurements on CaTi1?xFexO3?δ (x=0.1, 0.2, 0.3) were performed on polycrystalline pressed and sintered tablets using the van der Pauw four point method in controlled atmospheres. The results were interpreted to reflect n-type, ionic and p-type conductivity at different oxygen partial pressures. An increasing iron content increases the number of oxygen vacancies and increases the ionic conductivity at high temperatures, but also increases the tendency of ordering, which suppresses the ionic conductivity at more moderate temperatures. These findings are in accordance with the phase diagram of the system CaTiO3-CaFeO2.5 based on X-ray and Mössbauer studies. 相似文献
992.
Hans‐Christian Bttcher Marion Graf Kurt Merzweiler Christoph Wagner 《无机化学与普通化学杂志》2001,627(5):903-908
Heterobinuclear Complexes: Synthesis and X‐ray Crystal Structures of [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)], [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐Ph2PCH2PPh2)], and [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)] [Ru3Rh(CO)7(μ3‐H)(μ‐PtBu2)2(tBu2PH)(μ‐Cl)2] ( 2 ) yields by cluster degradation under CO pressure as main product the heterobinuclear complex [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)] ( 4 ). The compound crystallizes in the orthorhombic space group Pcab with a = 15.6802(15), b = 28.953(3), c = 11.8419(19) Å and V = 5376.2(11) Å3. The reaction of 4 with dppm (Ph2PCH2PPh2) in THF at room temperature affords in good yields [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐dppm)] ( 7 ). 7 crystallizes in the triclinic space group P 1 with a = 9.7503(19), b = 13.399(3), c = 15.823(3) Å and V = 1854.6 Å3. Moreover single crystals of [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 9 ) could be obtained and the single‐crystal X‐ray structure analysis revealed that 9 crystallizes in the monoclinic space group P21/a with a = 11.611(2), b = 13.333(2), c = 18.186(3) Å and V = 2693.0(8) Å3. 相似文献
993.
Sheng‐Shu Hou Robert Graf HansWolfgang Spiess Ping‐Ling Kuo 《Macromolecular rapid communications》2001,22(17):1386-1389
Microstructure and phase behavior of a semi‐interpenetrating polymer network consisting of 10% poly(ethylene oxide) and 90% crosslinked‐silicone have been studied using various 1H solid‐state NMR methods under fast magic angle spinning in combination with well‐known polymer characterization techniques. Both, 1H double‐quantum MAS NMR spectroscopy as well as NOESY MAS measurements indicate a mixing of the two components on a molecular level. 相似文献
994.
995.
E. Gebhardt E. Graf E. J. Verspohl E. Graf E. Graf E. Graf 《Chemie in Unserer Zeit》1991,25(2):xi-xiii
996.
997.
Marion Herrig 《Chemie in Unserer Zeit》1993,27(5):245-245
998.
沈应中 Marion Leschke Stefan E. Schulz Ramona Ecke Thomas Gessner Heinrich Lang 《无机化学学报》2004,20(11):1257-1264
合成了一系列三正丁基膦辅助配体稳定的铜(Ⅰ)β-二酮配合物,对合成的配合物用元素分析、红外、核磁共振以及热重和差热等手段进行了表征。筛选出性能优良的配合物为前驱物用化学汽相沉积(CVD)的方法生长出金属铜膜,用SEM和EDX等手段对生长的铜膜进行了表征。 相似文献
999.
Fathi Emhemmed Minjie Zhao Selvi Yorulmaz Damien Steyer Celine Leitao Marion Alignan Muriel Cerny Alexandra Paillard Franck Milone Delacourt Diane Julien-David Christian D. Muller 《Molecules (Basel, Switzerland)》2022,27(4)
In recent years, interest in Cannabis sativa L. has been rising, as legislation is moving in the right direction. This plant has been known and used for thousands of years for its many active ingredients that lead to various therapeutic effects (pain management, anti-inflammatory, antioxidant, etc.). In this report, our objective was to optimize a method for the extraction of cannabinoids from a clone of Cannabis sativa L. #138 resulting from an agronomic test (LaFleur, Angers, FR). Thus, we wished to identify compounds with anticancer activity on human pancreatic tumor cell lines. Three static maceration procedures, with different extraction parameters, were compared based on their median inhibitory concentration (IC50) values and cannabinoid extraction yield. As CBD emerged as the molecule responsible for inducing apoptosis in the human pancreatic cancer cell line, a CBD-rich cannabis strain remains attractive for therapeutic applications. Additionally, while gemcitabine, a gold standard drug in the treatment of pancreatic cancer, only triggers cell cycle arrest in G0/G1, CBD also activates the cell signaling cascade to lead to programmed cell death. Our results emphasize the potential of natural products issued from medicinal hemp for pancreatic cancer therapy, as they lead to an accumulation of intracellular superoxide ions, affect the mitochondrial membrane potential, induce G1 cell cycle arrest, and ultimately drive the pancreatic cancer cell to lethal apoptosis. 相似文献
1000.