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311.
312.
Anatoliy K. Prykarpatsky Nikolai N. BogoliubovJr. Jolanta Golenia 《International Journal of Theoretical Physics》2008,47(7):1919-1928
Symplectic and symmetry analysis for studying MHD superfluid flows is devised, a new version of the Z. Peradzyński (Int. J.
Theor. Phys. 29(11):1277–1284, [1990]) helicity theorem based on differential-geometric and group-theoretical methods is derived. Having reanalyzed the Peradzyński
helicity theorem within the modern symplectic theory of differential-geometric structures on manifolds, a new unified proof
and a new generalization of this theorem for the case of compressible MHD superfluid flow are proposed. As a by-product, a
sequence of nontrivial helicity type local and global conservation laws for the case of incompressible superfluid flow, playing
a crucial role for studying the stability problem under suitable boundary conditions, is constructed. 相似文献
313.
Helmut Goesmann Eberhard Matern Jolanta Olkowska‐Oetzel Jerzy Pikies Gerhard Fritz 《无机化学与普通化学杂志》2001,627(6):1181-1184
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXIII. Reactions of tBu2P–P=P(Me)tBu2 with (Et3P)2NiCl2 and [{η2‐C2H4}Ni(PEt3)2] tBu2P–P=P(Me)tBu2 ( 1 ) forms with (Et3P)2NiCl2 ( 2 ) and Na(Nph) the [μ‐(1,3 : 2,3‐η‐tBu2P4tBu2){Ni(PEt3)Cl}2] ( 3 ) as main product. Using Na/Hg instead as reducing agent the Ni0 compounds [{η2‐tBu2P–P}Ni(PEt3)2] ( 4 ), [{η2‐tBu2P–P=P–PtBu2}Ni(PEt3)2] ( 5 ) and [(Et3P)Ni(μ‐PtBu2)]2 ( 6 ) with four‐membered Ni2P2 ring result. [{η2‐C2H4}Ni(PEt3)2] yields with 1 also 4 . The compounds were characterized by 1H and 31P{1H} NMR investigations and 3 also by a single crystal X‐ray analysis. It crystallizes triclinic in the space group P 1 with a = 1129.4(2), b = 1256.8(3), c = 1569.5(3) pm, α = 72.44(3)°, β = 70.52(3)° and γ = 74.20(3)°. 相似文献
314.
Harald Krautscheid Eberhard Matern Jolanta Olkowska‐Oetzel Jerzy Pikies Gerhard Fritz 《无机化学与普通化学杂志》2001,627(5):999-1002
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXV. Formation and Structure of [{ cyclo ‐P3(PtBu2)3}{Ni(CO)2}{Ni(CO)3}] tBu2P–P=P(R)tBu2 (R = Br, Me) reacts with [Ni(CO)4] yielding [{cyclo‐P3(PtBu2)3}{Ni(CO)2}{Ni(CO)3}]. The two cis‐tBu2P substituents of the cyclotriphosphane, which results from the trimerization of the phosphinophosphinidene tBu2P–P, are coordinating to a Ni(CO)2 unit forming a five‐membered P4Ni chelate ring. The trans‐tBu2P group is linked to a Ni(CO)3 unit. The compound crystallizes in the orthorhombic space group Pbca (No. 61) with a = 933.30(5), b = 2353.2(1) and c = 3474.7(3) pm. 相似文献
315.
Zyta Ziora Alina Maly Barbara Lejczak Pawel Kafarski Jolanta Holband Grayna Wjcik 《Heteroatom Chemistry》2000,11(3):232-239
Reaction of commercially available trialkyl phosphites with N‐phthalylamino acids gave mixtures of seven products, whereas the same reaction carried out with pure triethyl phosphite yielded only the desired 2‐(N‐phthalylamino)‐1‐oxoalkanephosphonates. These compounds underwent rearrangement to the same types of products that were obtained with the commercial phosphites. This latter series of reactions was promoted by the presence of dialkyl phosphites. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:232–239, 2000 相似文献
316.
Nowadays, more and more attention is paid to the development and the intensification of the use of renewable energy sources. Hemp might be an alternative plant for bioenergy production. In this paper, four varieties of Polish industrial hemp (Białobrzeskie, Tygra, Henola, and Rajan) were investigated in order to determine which of them are the most advantageous raw materials for the effective production of bioethanol. At the beginning, physical and chemical pretreatment of hemp biomass was carried out. It was found that the most effective is the alkaline treatment with 2% NaOH, and the biomasses of the two varieties were selected for next stages of research: Tygra and Rajan. Hemp biomass before and after pretreatment was analyzed by FTIR and SEM, which confirmed the effectiveness of the pretreatment. Next, an enzymatic hydrolysis process was carried out on the previously selected parameters using the response surface methodology. Subsequently, the two approaches were analyzed: separated hydrolysis and fermentation (SHF) and a simultaneous saccharification and fermentation (SSF) process. For Tygra biomass in the SHF process, the ethanol concentration was 10.5 g∙L−1 (3.04 m3·ha−1), and for Rajan biomass at the SSF process, the ethanol concentration was 7.5 g∙L−1 (2.23 m3·ha−1). In conclusion, the biomass of Polish varieties of hemp, i.e., Tygra and Rajan, was found to be an interesting and promising raw material for bioethanol production. 相似文献
317.
Renata Paprocka Leszek Pazderski Liliana Mazur Magorzata Wiese-Szadkowska Jolanta Kutkowska Michalina Nowak Anna Helmin-Basa 《Molecules (Basel, Switzerland)》2022,27(9)
1H-pyrrole-2,5-dione derivatives are known for their wide range of pharmacological properties, including anti-inflammatory and antimicrobial activities. This study aimed to synthesize new 3,4-dimethyl-1H-pyrrole-2,5-dione derivatives 2a–2f in the reaction of N3-substituted amidrazones with 2,3-dimethylmaleic anhydride and evaluate their structural and biological properties. Compounds 2a–2f were studied by the 1H-13C NMR two-dimensional techniques (HMQC, HMBC) and single-crystal X-ray diffraction (derivatives 2a and 2d). The anti-inflammatory activity of compounds 2a–2f was examined by both an anti-proliferative study and a production study on the inhibition of pro-inflammatory cytokines (IL-6 and TNF-α) in anti-CD3 antibody- or lipopolysaccharide-stimulated human peripheral blood mononuclear cell (PBMC) cultures. The antibacterial activity of compounds 2a–2f against Staphylococcus aureus, Enterococcus faecalis, Micrococcus luteus, Esherichia coli, Pseudomonas aeruginosa, Yersinia enterocolitica, Mycobacterium smegmatis and Nocardia corralina strains was determined using the broth microdilution method. Structural studies of 2a–2f revealed the presence of distinct Z and E stereoisomers in the solid state and the solution. All compounds significantly inhibited the proliferation of PBMCs in anti-CD3-stimulated cultures. The strongest effect was observed for derivatives 2a–2d. The strongest inhibition of pro-inflammatory cytokine production was observed for the most promising anti-inflammatory compound 2a. 相似文献
318.
Jolanta Słomińska 《manuscripta mathematica》2001,104(1):21-38
Let ? be a small category. We present some results which describe cohomology groups and homotopy colimits of functors defined
over ? using cohomology groups and homotopy colimits over certain categories associated to functors from ? to posets.
Received: 3 May 1999 相似文献
319.
Karolina Drek Joanna Kozowska Anna Detman Jolanta Mierzejewska 《Molecules (Basel, Switzerland)》2021,26(23)
2-Phenylethanol (2-PE) is an alcohol with a rosy scent and antimicrobial activity, and therefore, it is widely used in the food and cosmetic industries as an aroma and preservative. This work was aimed to draw up a technology for 2-PE bioproduction on whey permeate, which is waste produced by the dairy industry, rich in lactase and proteins. Its composition makes it a harmful waste to dispose of; however, with a properly selected microorganism, it could be converted to a value-added product. Herein, two yeast Kluyveromyces marxianus strains and one Kluyveromyces lactis, isolated from dairy products, were tested for 2-PE production, firstly on standard media and then on whey permeate based media in batch cultures. Thereafter, the 2-PE bioproduction in a continuous system in a 4.8 L bioreactor was developed, and subsequently, the final product was recovered from culture broth. The results showed that the yield of 2-PE production increased by 60% in the continuous culture compared to batch culture. Together with a notable reduction of chemical oxygen demand for whey permeate, the present study reports a complete, effective, and environmentally friendly strategy for 2-PE bioproduction with a space-time yield of 57.5 mg L−1 h−1. 相似文献
320.
Hamsa Subramanian Jolanta B. Lagowski 《International journal of quantum chemistry》1998,66(3):229-240
In this work, we present theoretical evidence illustrating that cyano derivatives of conducting polymers such as polythiophene, polycyclopentadiene, and polyfulvene have smaller intrinsic band gaps than those of their parent polymers. The geometric and electronic properties of the parent and the derivative polymers were studied with the use of two methodologies: (1) the pseudo-one-dimensional band-structure calculations performed using the semi-empirical molecular orbital theory (MNDO, AM1) and (2) oligomer calculations performed using the ab initio molecular orbital theory both at the Hartree–Fock and configuration interaction levels. In particular, we found that an organic polymer, poly(dicyanomethylene cyclopentadifulvene) (PCNFv), has a comparable (possibly lower) band gap to the one observed in poly(dicyanomethylene cyclopentadithiophene) (PCNTH) (which has a band gap of 0.8 eV). The precursor of PCNFv is poly(dicyanomethylene cyclopentadicyclopentadiene) (PCNCY) in which two cyclopentadiene rings are connected by a dicyanomethylene group. The additional bond conjugation (in contrast to PCNCY) perpendicular to the chain axis makes PCNFv very rigid and fully planar. Trends in structural properties indicate that the lower band gaps in the cyano-substituted polymers, in comparison to their parent polymers, are accompanied by a decrease in bond alternations in the aromatic or trans–cisoid forms and by an increase in bond alternations in the quinoid or cis–transoid forms. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66 : 229–240, 1998 相似文献