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Photoaddition of chloroform to ketones via a singlet exciplex: A photo-CIDNP study

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Chinese Journal of Chemistry 1991年第1期9卷 54-59页

作者： ZHANG Mao-Xi YANG Li liu Zhong-Li liu you-cheng The National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu730000

Photolysis of 4-acetyl-4-ethoxyformylcyclohexanone, 4-acetyl-4-phenylcyclohexanone and 1-acetyl-1-phenylcyclohexane in deuteriochloroform using a high pressure Hg-Xe lamp showed unusual polarizations. The results are explained by the formation of a singlet exciplex of the ketone with deuteriochloroform and the photoaddition of deuteriochloroform to the ketone.

关键词： A photo-CIDNP study Photoaddition of chloroform to ketones via a singlet exciplex CIDNP

Interaction of cyclodextrins with 1,3-di(1-naphthyl)propane and the additive effects of ionic surfactants

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Chinese Journal of Chemistry 1991年第6期9卷 512-514,516-520页

作者： XIE Rui-Qiang LEI Xue-Gong liu you-cheng Department of Chemistry Lanzhou UniversityLanzhou 730000

The interaction between cyclodextrins (CDs) and 1,3-di(1-naphthyl)propane (1) in aqueous methanol (V: V=1:1) has been investigated by means of fluorescence emission and UV absorption. Fluorescence enhancement and absorption spectra reveal that β- or γ-CD can form inclusion complexes with 1, but α-CD cannot. One of these complexes is identified as ground state complex (2:1), i.e. the eclipsed conformer of 1 is included. Molecule 1 can be driven out of the CD cavity by sodium dodecylsulfate (SDS) molecule, but cannot by cetyltrimethylammonium bromide (CTAB) or sodium cetylsulfate (SCS) molecules due to their alkyl chain coiling.

关键词： CD naphthyl)propane and the additive effects of ionic surfactants Interaction of cyclodextrins with 1,3-di

A Study of the Driving Force for Inclusion Complexation of α- and β- Cyclodextrin with Substituted Benzene

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Chemical Research in Chinese Universities 1999年第1期15卷 19-24页

作者： ZHANG Hai-ming LUO Shuang-hui CHEN Chao liu Lei GUO Qing-xiang liu you-cheng Department of Chemistry University of Science and Technology of ChinaHefei230026 National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou730000

The driving force for inclusion complexation of α and β CD with substituted benzene(PhX) was studied by means of step wise regression analysis. A set of multiple regression equations was established with correlation coefficients 0 96 and 0 94 for the individual complexation of α CD and β CD with PhX. The ln K a(calc.) values calculated with the aid of the regression equations were close to those determined experimentally. The inclusion complexation is dominantly driven by van der Waals force and hydrophobic interactions.

关键词： Cyclodextrin Driving force Inclusion Regression Substituted benzene

Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin

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Petroleum Science 2024年第1期21卷 87-99页

作者： Yan-Nan Du Kong-you Wu Yin liu Yan-Ying Li Zi-cheng Cao you-Wei Cui Jun liu Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina Exploration and Development Research Institute SINOPEC Northwest Oilfield BranchUrumqi 830011XinjiangChina The Fifth Gas Production Plant Changqing OilfieldPetroChinaXi'an 710018ShaanxiChina

With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention *** by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related *** contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon *** this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim ***-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic ***,the stress state of each point of the STGs was calculated using seismic curvature ***,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were *** results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped *** STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both *** shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient *** study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area.

关键词： Tarim Basin Sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control

Aggregation of 1,3-di(a-naphthyl)propane and di(a-naphthylmethyl)ethet in aqueousbinary solvents

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Chinese Journal of Chemistry 1990年第4期8卷 375-383页

作者： LEI, Xue-Gong liu, you-cheng Department of Chemistry, Lanzhou University, Lanzhou 730000 Department of Chemistry Lanzhou University Lanzhou 730000

The UV absorption and fluorescence spectra of 1,3-di (α-naphthyl) propane (1), di (α- naphthylmethyl) ether (2), and α-methylnaphthalene (3) in aqueous methanol, ethanol, and DMSO were recorded as a function of Φ value (fraction of water in binary solvents). The existence of two sta- tes, a metastable state (defined as m) and a stable stationary state (defined as s), of molecules 1 as well as 2 in the above cosolvents at high Φ was shown by the contrary fluorescence excimer to monomer intensity (Ie/Im)vs. Φ relationships of the samples prepared with different processes. On the basis of the Φ value, substrate concentration, and the temperature dependence of the UV spectra. fluores- cence excitation and emission spectra, the chromophores of 1, 2 show the formation of aggregates in ground state at high Φ owing to the hydrophobic interaction. The m states consist of a supersaturated solution with aggregates, whereas the s states are suspended microcrystals or micro-oil-droplets with aggregates. The conformations of the molecules in the aggregates were discussed. Single crystal X-ray structure of 2 is reported.

关键词： a-naphthylmethyl)ethet in aqueousbinary solvents Aggregation of 1,3-di a-naphthyl)propane and di

Electron transfer reactions between vinylmagnesium bromide and phenyl-substituted methyl chlorides

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Chinese Journal of Chemistry 1986年第1期4卷 20-28页

作者： liu you-cheng DANG Hai-Shan Department of Chemistry, Lanzhou University, Lanzhou Department of Chemistry Lanzhou University Lanzhou

The reaction of vinylmagnesium bromide （1） with trityl chloride （2） was investigatedand the products were identified as triphenylmethane （3）（81%）, acetylene （4）（74%）, trityl peroxide（6）（4%）, and minute amounts of triphenylpropene （7） and p-diphenylmethyltetraphenylmethane（8）. The results indicate that 1 possesses reducing property. The reaction mixture showed an ESRspectrum identical with that for trityl radical and the CIDNP of enhanced absorption for 4-H of1-diphenylmethylene-4-trityl-2, 5-cyclohexadiene （9）. Trapping experiment with styrene decreasedthe amount of 3 but had no effect on the formation of 4. The reducing property of 1 is discussedand one electron transfer mechanism for the reaction of 1 with 2 is proposed. S-T0mixing betweentrityl and MgBr occurred and the coupling of polarized trityl radical with another trityl radical resultedin the formation of polarized dimeric product. The different character between the reaction of 1 and 2and that of 1 and diphenylmethyl chloride （10） may be rationalized by the different electron-acceptingabilities between 2 and 10. The origin of CIDNP effect shown by the product tetraphenylethane（Ⅱ） for the reaction of 1 with 10 is also explained according to Kaptein's sign rule.

关键词： Electron transfer reactions between vinylmagnesium bromide and phenyl-substituted methyl chlorides CIDNP

Microenvironmental control of photochemica reactions Ⅱ.Fluorescence quenching of naphthalene and 1,3-di-(a-naphthyl)propane by RNA and bases in aqueous methanol

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Chinese Journal of Chemistry 1990年第4期8卷 340-349页

作者： LEI, Xue-Gong XIE, Rui-Qiang liu, you-cheng Department of Chemistry, Lanzhou University, Lanzhou 730000 Department of Chemistry Lanzhou University Lanzhou 130000

The fluorescence quenching of naphthalene (2)and 1, 3-di(α-naphthyl)propane (1) by RNA and bases in methanol-water (v:v=1:1) binary solvents in the presence or absence of cyclodex- trin (CD) has been investigated. The results show that both the monomer and excimer fluorescence of 1 can be quenched by these quenchers. The quenching and rates depend on the quencher and tem- perature. It is shown that there is a critical temperature (Tc) for each quencher. Below Tc, the excimer fluorescence spectra show vibrational structures and the Stern-Volmer plots are straight lines (for ura- cil and cytosine); while above the Tc, the vibrational structures disappear and the Stern-Volmer plots deviate from linearity and curve upward. The former is a static process; while the latter is a mixture of both static and dynamic processes. The addition of α-CD has no effect on the fine structure, whereas β-CD prevents the appearance of this structure efficiently. The quenching rates both for the monomer and excimer of 1 by bases except cytosine in the presence of β-CD at ambient temperature are not changed; the quenching of fluorescence of 1 by RNA in the presence of β-CD, however, is hindered. Time-resolved fluorescence study shows that the excimer fine structures appear from the zero time. The intensity of fine structures depend on the fraction of water (φ) in binary solvents, and it is independent of the pH value of the solvents. It is suggested that bases and RNA induced aggregates (perhaps microcrystal) are formed, in which the motion of molecules 1 is limited.

关键词： Fluorescence quenching of naphthalene and 1,3-di Microenvironmental control of photochemica reactions RNA

The effects of various factors on spontaneous imbibition in tight oil reservoirs

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Petroleum Science 2024年第1期21卷 315-326页

作者： cheng liu Tian-Ru Wang Qing you Yue-Chun Du Guang Zhao Cai-Li Dai School of Energy Resources China University of GeosciencesBeijing100083PR China School of Petroleum Engineering China University of PetroleumQingdao266580ShandongPR China

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

关键词： Tight oil reservoir Spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree

Studies on the kinetics of decomposition of diacyl peroxides——VI. CIDNP in the products of thermolysis of lauroyl peroxide and 3,5,5-trimethylhexanoyl peroxide

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Chinese Journal of Chemistry 1986年第2期4卷 116-122页

作者： LEI Xue-Gong GUO Qing-Xiang liu you-cheng*, Department of Chemistry, Lanzhou University, Lanzhou Department of Chemistry Lanzhou University Lanzhou

The1H NMR spectra recorded during the thermolysis of lauroyl peroxide and of 3,5,5-trimethylhexanoyl peroxide in ODCB containing 2-iodopropane show CIDNP multiplet effect. It wasobserved that the relative concentrations of 1-iodoundecane and 2-iodopropane. both polarized andnormal species. changed with time. The relaxation time T1of the a-protons in 1-iodoundecaneand vinyl protons of CH2in 1-undecene, enhancement factor of the protons of polarized species andthe rate constant of decomposition for lauroyl peroxide have been determined. The mechanismof the decomposition of the entitled peroxides is discussed in terms of the radical pair theory.

关键词： CIDNP in the products of thermolysis of lauroyl peroxide and 3,5,5-trimethylhexanoyl peroxide Studies on the kinetics of decomposition of diacyl peroxides VI