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The selection and utilization of ornamental plants that are highly tolerant to salt are helpful for landscape construction and the ecological protection of coastal and arid areas. To evaluate salt tolerance, one of the most used methods is the observation of seed germination under salt stress. Therefore, this work aimed to evaluate the influence of different concentrations of NaCl in water absorption, germination, and respiratory metabolism in seeds of different Flueggea suffruticosa genotypes. P2 and P27, salt-sensitive and salt-tolerant line s of F. suffruticosa, were chosen for treatment with 0, 40, 80, 120, 160, 200, and 240 mM NaCl. F. suffruticosa under salt stress exhibited inhibition of seed germination. The seeds of F. suffruticosa have different times for the physiological phases of water absorption with different NaCl concentrations. Salt stress retarded the seed water absorption process, and it depended on seed genotypes for F. suffruticosa. Soluble sugars accumulated in both P2 and P27 under salt stress. Meanwhile, the activities of hexokinase, 6-phosphofructokinase, pyruvate kinase, pyruvate dehydrogenase, citrate synthase, and glucose-6-phosphate dehydrogenase were overall increased in P27 after salt treatment, which caused increases in pyruvic acid and citric acid. The citrate synthase and glucose-6-phosphate dehydrogenase activities decreased in P2. These results suggest that the respiratory metabolism of salt-tolerant F. suffruticosa was enhanced, compared with the salt-sensitive line, to ameliorate the repression of seed germination under salt stress. The different changes in respiratory metabolism could influence the degree of salt tolerance.

Distribution characteristics, organic matter development characteristics, gas-bearing characteristics, reservoir characteristics, and preservation conditions of the Shahezi Formation shale of Lower Cretaceous in the Lishu fault depression, Songliao Basin, NE China, are analyzed using organic geochemical, whole rock, and SEM analysis data, and CO2 and N2 adsorption and high-pressure mercury injection experiment data in combination with the tectonic and sedimentation evolution of the region to reveal the geological conditions for enrichment and resource potential of continental shale gas. The organic-rich shale in the Lower Cretaceous of the Lishu fault depression is mainly developed in the lower submember of the second member of the Shahezi Formation (K1sh21 Fm.) and is thick and stable in distribution. The shale has high TOC, mainly types II1 and II2 organic matter, and is in the mature to the over-mature stage. The volcanic activity, salinization, and reduction of the water environment are conducive to the formation of the organic-rich shale. The shale reservoirs have mainly clay mineral intergranular pores, organic matter pores, carbonate mineral dissolution pores, and foliated microfractures as storage space. The pores are in the mesopore range of 10–50 nm, and the microfractures are mostly 5–10 μm wide. Massive argillaceous rocks of lowland and highstand domains are deposited above and below the gas-bearing shale separately in the lower submember of the K1sh21 Fm., act as the natural roof and floor in the process of shale gas accumulation and preservation, and control the shale gas enrichment. Based on the above understandings, the first shale gas exploration well in Shahezi Formation was drilled in the Lishu fault depression of Songliao Basin. After fracturing, the well tested a daily gas production of 7.6×104 m3 marking a breakthrough in continental shale gas exploration in the Shahezi Formation (K1sh Fm.) of the Lishu fault depression in Songliao Basin. The exploration practice has reference significance for the exploration of continental shale gas in the Lower Cretaceous of Songliao Basin and its periphery.

Pure shales in the first member of Qingshankou Formation (simplified as Qing 1 Member) in the southern Songliao Basin, i.e., the semi-deep and deep lacustrine shales, are characterized by a high content of clay minerals and poor hydrocarbon mobility, making the development of shale oil difficult. According to the drilling and testing results, the shale of Qing 1 Member can be classified into 3 lithofacies, i.e., bedded argillaceous shale, laminated diamictite shale, and interbedded felsic shale. The TOC and brittle minerals control the enrichment of shale oil, of them, TOC controls the total oil content, in other words, the total oil content increases with the increase of TOC; while the laminae made up of brittle minerals contain a large number of bigger intergranular pores which are favorable enrichment space for movable shale oil. In consideration of the origins of the 3 lithofacies, two shale oil enrichment models are classified, i.e., the deep lacustrine high-TOC bedded argillaceous shale (Model-I) and the semi-deep lacustrine moderate-high-TOC laminated diamictite shale (Model-II). In the Model-I, the shale is characterized by high hydrocarbon generation ability, high total oil content, abundant horizontal bedding fractures, and vertical and high angle fractures locally; the complex fracture network formed by horizontal bedding fractures and vertical fractures improve the storage capacity and permeability of the shale reservoir, increase the enrichment space for movable oil. In the Model-II, the shale is characterized by good hydrocarbon generation ability and fairly high total oil content, and as the brittle laminae contain large intergranular pores, the shale has a higher movable oil content. Based on the two models, shale oil sweet-spot areas of 2880 km2 in the southern Songliao Basin are favorable for further exploration. Aimed at the difficulties in reservoir fracturing of the lacustrine shale with a high content of clay minerals, the composite fracturing technology with supercritical carbon dioxide was used in the shale oil reservoir for the first time, realizing large-scale volume fracturing in shale with a high content of clay minerals and strong heterogeneity, marking a breakthrough of oil exploration in continental shale with a high content of clay minerals in China.

Abstract: Taking the inter-salt organic-rich shales in the third member of Paleogene Shahejie Formation (Es3) of Dongpu sag in Bohai Bay Basin as an example, the origin of overpressure, development characteristics, formation and evolution mechanism, formation stages and geological significance on shale oil and gas of overpressure fractures in the inter-salt shale reservoir were investigated by means of thin section identification, scanning electron microscopy observation, analysis of fluid inclusions, logging data analysis, and formation pressure inversion. The results show that overpressure is universal in the salt-lake basin of Dongpu sag, and under-compaction caused by the sealing of salt-gypsum layer, pressurization due to hydrocarbon generation, transformation and dehydration of clay minerals, and fault sealing are the 4 main factors leading to the occurrence of overpressure. The overpressure fractures are small in scale, with an average length of 356.2 μm and an average underground opening of 11.6 μm. But they are densely developed, with an average surface density of 0.76 cm/cm2. Moreover, they are often accompanied by oil and gas charging, and thus high in effectiveness. Overpressure fractures were mainly formed during two periods of large-scale oil and gas charging, approximately 25–30 Ma ago and 0–5 Ma ago. Inter-salt overpressure fractures play dual roles as the storage space and migration paths of shale oil and gas. They contribute 22.3% to the porosity of shale reservoir and 51.4% to the permeability. They can connect fracture systems of multiple scales, greatly improving the quality of shale reservoir. During the development of shale oil and gas, inter-salt overpressure fractures can affect the extension and morphology of hydraulic fractures, giving rise to complex and highly permeable volumetric fracture networks, improving hydraulic fracturing effect and enhancing shale oil and gas productivity.

Using geochemistry, sedimentary and petroleum geology methods, and based on the analysis of spatial distribution of deep source rocks and sedimentary organic facies, the favorable exploration prospects in the Jiyang Depression, Shengli Oilfield are studieded. There are 4 types of sedimentary organic facies (including anoxic organic facies, anaerobic organic facies, dysaerobic organic facies and aerobic organic facies) in deep source rocks of Kongdian Formation - Sha-4 Member, Paleogene. The source rocks of Anoxic facies and anaerobic facies are discovered in the Sha-4 Member and are proved as excellent source rocks, while the Kongdian Formation source rocks compose mainly of the dysaerobic facies and aerobic facies and served as common source rocks. The whole hydrocarbon expulsion process is divided into 3 stages, including free water expulsion, hydrocarbon generation and energy accumulation, and hydrocarbon expulsion from microfractures. The hydrocarbon expulsion from deep source rocks mainly occurs in the stage of hydrocarbon expulsion from microfractures, during which there are three oil and gas migration modes with different geologic conditions, including vertical migration, lateral migration and downward migration. The studies indicated that the hydrocarbons in shallow and medium formations from the Sha-4 Member excellent source rocks of anoxic and anaerobic facies are mainly accumulated through vertical migration along the faults, while the reservoirs formed by lateral migration and downward migration are still waiting to be revealed. So there is great exporation potential for the deep Paleogene of the Jiyang Depression. Key words: Jiyang Depression, Paleogene, organic facies, hydrocarbon generation and expulsion mechanism, hydrocarbon migration, accumulation

In the title molecule, C24H32N4O2, the piperazine ring adopts a chair conformation and the dihedral angle between the two benzene rings is 35.4 (1)°. In the crystal structure, intermolecular O—H...N hydrogen bonds link molecules into chains along [001].

In the title compound, [Zn(C15H11N2O2)2(C2H8N2)], the ZnII atom is coordinated in a distorted tetrahedral geometry. Intramolecular N—H...O, C—H...O and C—H...N hydrogen bonds occur. In the crystal, molecules are linked by intermolecular N—H...O hydrogen bonds, forming a three-dimensional network.

The asymmetric unit of the title complex, [Ni(pht)2(pn)2] (pht is 5,5-diphenylhydantoinate and pn is propane-1,2-diamine) or [Ni(C15H11N2O2)2(C3H10N2)2], contains one-half [Ni(pht)2(pn)2] molecule. The NiII atom is situated on a crystallographic center of inversion and shows a distorted octahedral coordination geometry. A three-dimensional network structure is assembled by inter- and intramolecular N—H...O=C interactions.

The title compound, C2H10N22+·2C10H9N2O−, is composed of deprotonated 5-methyl-2-phenyl-1H-pyrazol-3(2H)-one anions (PMP−) and protonated ethylenediamine cations (H2en2+). The ethylenediammonium ion is located on a crystallographic inversion center. The dihedral angle between the phenyl and pyrazole rings is 39.73 (8)°. The two components are connected through N—H...O and N—H...N hydrogen bonds, forming an infinite three-dimensional network.

Rhodamine 6G (R6G), a well-known fluorescent dye, has been intercalated into layered potassium titanoniobate (KTiNbO) through a guest-guest exchange method by using propylammonium titanoniobate (PrNH-TiNbO) as a precursor. The synthesis process, the structure and morphology characterizations for lamellar nanocomposite have been investigated by means of XRD, FTIR, and SEM. The thermostability of R6G-TiNbO nanocomposite is discussed on the basis of thermogravimetric and calorimetric techniques. Absorption and fluorescence techniques are applied to study the photoresponse of R6G in hybrid film. The results indicate that R6G cations in thin film are highly fluorescent even at a high dye concentration, which may be due to the formation of J-dimers within the confined galleries. [ABSTRACT FROM AUTHOR]

Flowerlike CoO nanoparticles were used as a modifier on the glassy carbon electrode to fabricate a quercetin (Qu) sensor. The morphology and crystallinity of the prepared CoO material were investigated by scanning electron microscopy and X-ray diffraction. Electrochemical behavior of Qu at the sensor was studied by cyclic voltammetry and semi-derivative voltammetry. Results suggested that the modified electrode exhibited a strong electrocatalytic activity toward the redox of Qu. The electron transfer coefficient (α), the number of electron transfer ( n), and the diffusion coefficient ( D) of Qu at the sensor were calculated. Under the optimum conditions, the catalytic peak currents of Qu were linearly dependent on the concentrations of Qu in the range from 5.0 × 10 to 3.3 × 10 M, with a detection limit of 1.0 × 10 M. This proposed method was successfully applied to determine the quercetin concentration in Ginkgo leaf tablet and human urine samples. [ABSTRACT FROM AUTHOR]

Methylene blue (MB) was intercalated into layered potassium titanoniobate (KTiNbO5) through a guest–guest exchange method by use of the intercalation compound n-C4H9NH3 +–TiNbO5 as a precursor. The MB+/H+–TiNbO5 nanocomposite has been characterized by XRD, SEM, IR, TGA, UV, elemental analysis, and electrochemical cyclic voltammetric measurements. From the XRD and elemental analysis results, we proposed that the MB+ cations formed a single layer standing vertically to the titanoniobate nanosheets together with H+. The CV curves of the MB+/H+–TiNbO5 nanocomposite thin film exhibited a fine diffusion-controlled redox process, which hints the possibility of being utilized as an electrode modifying material. [ABSTRACT FROM AUTHOR]

Bowknot-like CeO2 bundles crystals were successfully prepared from a single precursor via a thermal decomposition route. The precursor was synthesized by a hydrothermal reaction using Ce(NO3)3 · 6H2O with CO(NH2)2 at 150 °C in a water-glycerol complex solution. Glycerol plays a very important role for the formation of precursor bowknot-like structures. The morphology of the precursor was maintained during the heating process. The optical absorption spectrum indicates that the CeO2 dendrites have a direct band gap of 3.42 eV, which is mostly larger than values of bulk powders due to the quantum size effect. The electrochemical characters of the CeO2 bundles structures are studied by their investigation of cyclic voltammetry (CV). It was found that the CeO2 bundles can greatly improve the electron transfer ability. [ABSTRACT FROM AUTHOR]

A novel modified glassy carbon electrode (GCE) with a binuclear copper complex was fabricated using a cyclic voltammetric method in phosphate buffer solution. This modified electrode shows very efficient electrocatalytic activity for anodic oxidation of both dopamine (DA) and ascorbic acid (AA) via substantial decrease in anodic overpotentials for both compounds. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) using this modified electrode show two well-resolved anodic waves for the oxidation of DA and AA in mixed solution, which makes it possible for simultaneous determination of both compounds. Linear analytical curves were obtained in the ranges 2.0–120.0 μM and 5.0–160.0 μM for DA and AA concentrations by using DPV methods, respectively. The detection limits were 1.4 × 10−6 M of DA and 2.8 × 10−6 M of AA. This electrode was used for AA and DA determinations in medicine and foodstuff samples with satisfactory results. [ABSTRACT FROM AUTHOR]