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L. japonica has been used as food and healthy beverage due to the good nutrition. Although the chemical compounds have been extensively studied, polysaccharide compositions remain unclear. In this study, water-soluble polysaccharides of L. japonica were fractionated into one neutral fraction (LJP-N) and four acidic fractions (LJP-A-1 ~ LJP-A-4) by a combination of ion-exchange and gel permeation chromatographies. The structures and antioxidant activities of these factions were determined by HPLC, FT-IR and the radical scavenging activities, anti-hemolysis inhibitory ability, protective effect against DNA damage. Results showed that LJP-N was a starch-like glucan with some arabinogalactan; acidic fractions were all pectic polysaccharide, with the average molecular weights approximately ranging from 19.0 to 383.8 kDa. LJP-A-2 ~ LJP-A-4 were similar to each other, mainly composed of GalA (>50%) with some Gal and Ara residues, while LJP-A-1 mainly composed of Gal and Ara (>70%). LJP-A-3 was defined as HG-type pectic polysacchride, with a trace of RG-I domain by NMR experiment. The antioxidant activity of LJP fractions showed different activities, and LJP-A-3 and LJP-A-4 exhibited noticeable antioxidant activities by six kinds of evaluated methods comparable with others. The results indicated that LJP-A-3 and LJP-A-4 could be used as a potential natural source of antioxidant.

The control of coal fragmentation and fines generation during mining and processing is important in coal production. A method to characterise, model and simulate coal size degradation and fines generation based on lithotypes has been developed. This method was refined to cover both high energy single impact to mimic blasting and crushing and low energy incremental breakage to mimic coal handling, transiting, stockpiling and processing. The JKRBT was utilised to characterise high energy single impact breakage and drop shatter tests were used to characterise low energy incremental breakage. X-ray Computed Tomography (XCT) scanning was used as an undisruptive technique to estimate size distributions of drill cores in the drop shatter tests. The JK size-dependent breakage model was applied for breakage characterisation, size degradation modelling and fines generation simulation. The results indicate that coal lithotype has a significant influence on coal degradation and fines generation. This paper has demonstrated that the adaption of two distinct breakage characterisation tests and linkage via the one model is a significant advance in quantifying coal degradation and fines generation during coal production.

During its long process of serving time, roller compacted concrete (RCC) arch dam effected by the comprehensive combination of many factors shows a typical time-varying characteristic on its structure and material properties, which is objectively reflected in the prototype monitoring data. On the basis of the analysis on influence variables of dam deformation and the working mechanism of the RCC arch dam, in this paper, time-varying early-warning model for the RCC arch dam is established by introducing time-varying factors into hydrostatic pressure components and expanding temperature components, then the modeling method of time-varying early-warning model above is proposed combined with the partial least squares algorithm and genetic algorithm.

Apart from conventional gas in the middle-shallow formation in the Xihu depression in the East China Sea Basin, low permeability gas sandstone layers in the middle-deep formation have recently been discovered. On the basis of integrated analysis of reservoir petrology and diagenesis, geochemistry of gas and source rocks, basin numerical modeling, gold-tube pyrolysis experiment of rocks and fluid inclusion, a comprehensive investigation of the characteristics of low-permeability reservoirs, gas origin, generation and charge in the sub-structural belts (West Slope Belt and West Sub Sag) has been performed. Strong mechanical compaction, filar authigenic illite, siliceous and carbonate cements are key factors for the formation of low permeability reservoirs. The comprehensive analysis of molecular components, stable carbon isotope compositions of gases and light hydrocarbons indicated that the low permeability gases in the WSB are mainly coal-derived and can be divided into two types: (1) mature gases sourced from local coal-measure rocks in the Pinghu Formation, (2) exogenous highly mature gases sourced from the coal-measure rocks in the Pinghu Formation in the WSS. Mature gases were injected into the low permeability reservoirs in the middle-lower Pinghu Formation at approximately 2.8Ma∼0Ma. In the meantime, partial highly mature gases generated from source rocks in the WSS also migrated to the WSB. On the whole, the gas charge in the WSB is characterized by dual-sourcing and late-stage. The low permeability gases in the WSS almost are highly mature and composed of most coal-derived gases generated from local coal-measure rocks in the Pinghu Formation and a small amount of oil-derived gases generated from local dark mudstones containing sapropelic-type organic matters in the Pinghu Formation. In addition, mature coal-derived gases generated from source rocks in the lower Huagang Formation are also present but very limited. The charge of highly mature gases in the low permeability reservoirs in the lower Huagang Formation in the WSS occurred at approximately 3.9Ma∼0Ma.

The found gas pools in the Songdong and Baodao regions in the eastern Qiongdongnan basin, South China Sea have almost failed to realize expected commercial value due to either low reserve abundance or high carbon dioxide (CO2) content. To assist in further exploration, the genetic type, source and accumulation history of natural gas have been investigated based on the analysis of the chemical compositions, carbon isotopes and light hydrocarbons in gases, isotope compositions of rare gas, basin numerical modeling and fluid inclusion analysis. The results indicate that there are three representative types of gases. The first type distributed in the BD13 and ST24-1 areas consists of biogenic and oil-derived gases from the Songdong sag. The second type distributed in the BD19-2 area is composed of coal-derived and oil-derived gases from the Baodao sag. The third type distributed in the BD15-3, BD19-4 and BD19-2 areas consists of significant amounts of volcanic mantle-derived CO2 and few organic hydrocarbon gases. The charge of oil-derived gas and formation of biogenic gas are close to the deposition stage of overlying thick mudstones. This may be a critical factor for current gas pools with low reserve abundance in the Songdong region. Intense activity of the No.2 fault and absence of overlying thick mudstones gave rise to the escape of a large quantity of oil and gas from the middle Oligocene to middle Miocene. Besides, due to volcanic activity in the Quaternary, mantle-derived CO2 was injected into the reservoirs via No.2 fault. The previous accumulative hydrocarbon gases were driven off by CO2 in various degrees, which may be mainly responsible for current situation that most gas pools have high CO2 content in the Baodao region.

Tight oil sandstones have large oil reserves but low waterflooding efficiency and oil recovery. The movable oil saturation (MOS) is a critical parameter for evaluating oil recovery in water-driven tight oil sandstone reservoirs. However, its controlling factors in tight oil sandstones are still not well understood. In this study, the tight/low-permeability sandstones in the Chang 8 and Chang 9 Members of the Honghe Oil Field in the Ordos Basin (China) provide an opportunity to determine the effects of pore structure on the MOS. Porosity, permeability, thin sections, scanning electron microscopy (SEM), large field-of-view SEM imaging method (MAPS technique), high-pressure mercury intrusion (MICP), and micro-CT scanning were systemically conducted to analyze the pore structure analysis. MOS values were obtained from the relative permeability tests. The results show that porosity, pore-throat size, and the sorting coefficient have no evident relationship with the MOS. Many of the higher-permeability samples even show lower MOS values. Moreover, analysis of micro-CT images before and after waterflooding indicates that the lower-permeability samples tend to swept larger areas than the higher-permeability samples, resulting in greater oil-displacement efficiencies and MOS values. Instead, the cumulative mercury saturation at the apex of the mercury injection hyperbola curve (Sapex), the ratio of the maximum pore-throat radius and the medium pore-throat radius (Rmax/R50), and movable fluid saturation (MFS) show a good linear relationship with the MOS. The displaced oil is primarily from intergranular pores and partly from intragranular pores. The micropores that are widely distributed at the grain-grain contact display low original oil saturation and low oil displacement efficiency. It is proposed that the volume of the well-connected pores that contribute to permeability is the key factor controlling the MOS regardless of the type of rock.

Conventional coal washability analysis is achieved by conducting Float and Sink (FaS) test, which is sampling dependent, destructive and uses environmentally hazardous chemicals. With the improvement of modern 2D and 3D imaging technologies, image analysis methods of digital CT scanned images are being developed and trialled to predict coal washability in a more flexible, efficient and safe way. To support the validity of this approach, this study illustrates the fundamental differences in breakage and liberation behaviour of coal lithotypes at the same rank from a single seam. Nine lithotype samples were repeatedly CT scanned before and after a series of 2 m drops to emulate fragmentation during the drop shatter test. The 3D watershed segmentation method was applied to scans to monitor changes in fragment size distribution and then assign a density to each fragment to obtain coal washability. Comparison between the processed image analysis results and FaS tests conducted after 31 drops show a very good match both in particle size distribution and coal washability for all the lithotypes. Results also show that dull coal or stone illustrate better agreement between CT image analysis and FaS test due to their very low percentage of small particles which may lead to underestimation when using CT image analysis. Possible ways of improving small particles estimation would be to use an XY plane H-maxima method and low merging coefficient in the image analysis process.

The inter-salt shale-oil reservoir in Liutun Sag of the Dongpu Depression in the Bohai Bay Basin, China, has a strong overpressure and produces abundant heavy oil with little water. The previous researches claimed that the overpressure was mainly a result of disequilibrium compaction, which seemingly contradicts with the little water production. More systematic work is required to understand the origin of the overpressure and the oil/water production. Formation testing, mud weight and wireline-log data were used to recognize overpressure and equivalent depth method and sonic transit time-density crossplot were used to identify the overpressure mechanisms. In addition, the tectonic evolution was included in the analysis, aiming at understanding the oil/water production features. Disequilibrium compaction is considered as the main overpressure mechanism, due to the sealing of salt rocks. Hydrocarbon generation, which mainly generated low maturity heavy oil, contributes to the overpressure feature with the help of tectonic uplift. The overpressure evolution, which corresponds to the tectonic evolution, consists of three phases: early disequilibrium compaction, middle fluid substitution and late disequilibrium compaction. The tectonic uplift in the middle phase, it is proposed, contributes most to the little water production. With the tectonic uplift, a lot of fractures formed, which would promote oil and water drain. However, due to the low mobility of heavy oil, more water tended to be drained away from the region of strong overpressure, and thus the intuitive fluid substitution occurred. The findings above indicate that the exploration of inter-salt shale-oil reservoirs in Liutun Sag or even the other areas of Dongpu Depression may additionally consider some special strategies, including the occurrence of salt rocks and the hybrid overpressure feature of disequilibrium compaction and fluid expansion besides tectonic uplift.

The complexity of fracture networks in shale gas reservoirs may result from the superimposition of several fracture sets forming in temporally modified stress states during burial. In addition to tectonic evolution, this modification can also be caused by the overpressure generated by gas generation. Compared with undercompaction, gas generation shows a different overpressuring process and may cause different effects on stress states. This paper addresses these effects during burial in terms of pore pressure stress coupling. A series of finite element simulations for this investigation are designed with different tectonic stress regimes using a simplified model with a homogeneous poroelastic medium. The results show that during burial, gas generation not only significantly decreases effective stresses but also changes differential stress by decreasing it in the normal faulting regime and increasing it in the thrust faulting regime compared with undercompaction. Furthermore, gas generation during burial may locally transform the given tectonic stress regime from normal faulting to strike slip or even thrust faulting regimes. The investigation implies that gas generation rather than undercompaction in burial history can significantly diversify the patterns of natural fractures by affecting the differential stress and even the local stress regime in addition to influencing their spatial distribution due to its spatial heterogeneity and its different effects on stress states in different stress regimes. As a result, the contribution of gas generation to overpressures should be differentiated from that of undercompaction before analysing the effects of overpressures on natural fracture development.

Over the past 30 years, China’s urbanization has strongly supported the rapid growth and sustained transformation of economy; it has also led to a continuous increase in atmospheric environmental stress. A deep understanding of the coupling relationship between urbanization and air quality is essential for evaluating the quality of urbanization and long term sustainability. We first constructed a set of indexes to evaluate the extent of urbanization, and then used the global principal component analysis, harmony degree model, as well as the coupling coordination degree model and Geographic Information System (GIS) to explore the coupling relationship between urbanization and air quality in Shandong Province from 2014 to 2017. The results show that: (1) in 2014, cities with a high coupling coordination degree (D > 0.7) between urbanization and air quality index (AQI) as well as pollutants were mainly distributed in coastal regions of Shandong Province. The coupling relationships between urbanization and AQI and PM2.5 in part of central Shandong were basically uncoordinated (0.3

Understanding the reservoir quality and heterogeneity of tight oil sandstone reservoirs is essential for their exploration and production. An integration of lithological, diagenetic and hydrocarbon emplacement factors was analyzed to understand the reservoir quality difference in Chang 8 and Chang 9 sandstones of Yanchang Formation, Honghe Oil Field, Ordos Basin, using core, well logs, casting thin sections, SEM, cathode luminescence images and x-ray diffraction data. The results show that Chang 8 and Chang 9 sandstones are mainly fine to medium-grained feldspathic litharenites and lithic arkose with moderately well to well sorting, from braided-delta front subaqueous distributary channel facies. The average porosity and permeability of Chang 8 and Chang 9 sandstones are 8.52%, 0.27mD and 12.96%, 2.86mD, respectively. The main diagenesis types are mechanical compaction, authigenic chlorite, calcite cement, and dissolution. The Chang 8 and Chang 9 sandstone reservoir quality difference is mainly a result of the oil charging and diagenetic environment change. The Chang 8 sandstones that close to the source rock have a high content of feldspar and lithic dissolution and grain collapse from the acidic fluids injection, which dramatically decrease porosity and permeability. Whereas, the Chang 9 sandstones far from the NW-SE direction faults have a small amount of oil charging and acidic fluid injection, which result in high content of chlorite that narrow the throats and reduce permeability, but slightly reduce porosity. Only the sandstones at the bottom of Chang 8 or close to the NW-SE direction faults in Chang 9 Member have a small amount of acidic dissolution, medium content of chlorite, which lead to the relatively high porosity and permeability. High calcite cement contents are mainly observed at the top or bottom of the sandbody, which is not the main factor that leads to the Chang 8 and Chang 9 sandstone reservoir quality difference.

The tolerance of mycophenolate mofetil (MMF; Shanghai Roche, China) in Lee Classes III, IV, and V immunoglobulin A nephropathy (IgAN) remains unclear. This article reports nine cases of severe pneumonia (SP), including pneumocystis pneumonia (PCP) and cytomegalovirus (CMV) pneumonia, and its risk factors in MMF plus low-dose corticosteroid-treated patients with Lee Classes III, IV, and V IgAN. Fifty-three patients with IgAN were included in this single-center study. The treatment regimen was MMF (1–1.5 g/d) plus low-dose corticosteroids (0.5 mg/kg/d). SP was defined as diffuse bilateral lung infiltrate with respiratory failure. PCP was diagnosed by detecting the organisms in the sputum and bronchoalveolar lavage. CMV infection was diagnosed through serum screening for CMV-IgG and IgM antibodies and CMV-DNA testing by a real-time polymerase chain reaction assay. The risk factors of SP were analyzed. Nine cases (16.9%) of SP occurred in this study. All SP developed at approximately the 10th–14th week after the initiation of the regimen: PCP was diagnosed in four cases and CMV infection in two cases. Renal function impairing was more serious in patients with SP than in those without SP, as evidenced by estimated glomerular filtration rate (p = 0.019) and serum creatinine level (p = 0.016). Six of the nine SPs occurred in MMP plus low-dose methylprednisolone group, which was statistically higher than that in the MMF plus low-dose prednisone group (p = 0.000). The incidence of SP in this study was 16.9%. Chronically impaired renal function and the use of methylprednisolone may be the risk factors for SP.

In order to improve the overall electrochemical performances of La–Mg–Ni-based hydrogen storage alloy, electroless composite plating Ni–Cu–P treatment was applied to La0.88Mg0.12Ni2.95Mn0.10Co0.55Al0.10 alloy powders. SEM observation showed that the composite treatment resulted in spherical particles more densely depositing on the alloy surface, and subsequently EDS analysis indicated that the particles should be Ni–Cu-P compounds. These particle coatings enhanced the conductivity and the catalytic activity, besides acting as a protective layer, thereby improving the electrochemical properties of the alloy. The discharge capacity of the alloy electrode noticeably increased from 338 mA/g to 361 mA/g. The capacity retention after 200 charge/discharge cycles and the high rate dischargeability (HRD) at 1500 mA/g discharge current density of the alloy electrode increased from 76.0% and 27.7% to 84.8% and 37.0%, respectively. The superior HRD value is believed to be ascribed to the improved kinetics from the compact metallic layers on the surface.

The multi-photon dissociative photoionization dynamics of CF 3 I has been studied with femtosecond two-color pump–probe time-of-flight mass spectra at a pump pulse of 265 nm and a probe pulse of 398 nm. This enables the A band and 5 pπ 3 7 sσ ( 2 Π 1/2 ) Rydberg state to be accessed with the pump beam. The observed fast and slow decay components of CF 3 + and I + reflect the fast repulsive A band and some higher lying ion-pair states may be responsible for the decay of the 5 pπ 3 7 sσ ( 2 Π 1/2 ) Rydberg state. The results provide information on the different multi-photon pathways producing these ions and the de-excitation mechanism of the 5 pπ 3 7 sσ ( 2 Π 1/2 ) Rydberg state.

The Rydberg state decay dynamics of ammonia is investigated in real-time by (2+1 ′ ) femtosecond pump-probe ionization detection. The lifetime of ammonia in the E ′ 1 A 1 ′ state is determined as 936±92 fs for the first time. The internal conversion (IC) pre-dissociation mechanism of the E ′ 1 A 1 ′ state has been discussed in this report. Concurrently, the A 1 A 2 ′′ state ( ν 2 ′ =4) lifetime is estimated as 51±4 fs, which is identical with the previous reports.

With the high sensitivity and high resolution of the techniques of intracavity laser magnetic resonance spectroscopy, strong nonlinearity of the Zeeman effect in the NO molecule has been observed in a moderate external field. A fairly simple and effective method of modelling the 2nd order Zeeman effect without recoursing to full matrix diagonalization has been developed and successfully used to analyze the nonlinearity of Zeeman effect in this Letter. Results agree well with those calculated by matrix diagonalization of precise Halmiltonian in which the off-diagonal Zeeman interaction are included. (C) 2000 Elsevier Science B.V. All rights reserved.