Measurement of light polarization characteristics from an oil-polluted soil surface in near-infrared bands

Oil pollution can be monitored by infrared remote sensing technology. In this work, the degree of po-larization (DOP) was established as a quantitative index of oil pollution. The crude oil and the local typical surface soil from the Songyuan oil field in Jilin province were collected. Some soil samples with four levels of oil content and three levels of water content were prepared and measured. The DOP of the polluted soil and the clean soil in the field was also measured at 180° relative viewing azimuth a...     

Study on the hyperspectral polarized reflection characteristics of oil slicks on sea surfaces

This study is concerned with the need for remote sensing techniques for the monitoring of oil-slick pollution on sea surfaces and the effects of oil-slick pollution on the sea.We used Daqing crude oil,Jilin crude oil,heavy oil and seawater from Dalian Bay to simulate oil-slick pollution on the sea surface and obtained multi-angle hyperspectral polarized reflectance information,from which we calculated the polarization for different kinds of crude oil,and oil-slicks of different thicknesses.By comparing the degree of polarization between oil-slicks of different thickness,and sea water,it was found that in the case of thin oil-slicks,the degree of polarization of seawater is higher than that of oil slicks with wavelengths of between 400-1000 nm.However,there was little difference at a wavelength of 785 nm.At angles of incident of 20° and 30° (the viewing angle equals the incident angle),it was easy to distinguish the changes of oil-slick thickness by the degree of polarization at 785 and 880 nm in the near-infrared band.The crude oil showed its inherent polarized characteristic as the oil-slick thickness increased to a certain degree.That is to say,the polarization of the seawater was higher than that of the oil-slick in the visible light range,but less than that in the near-infrared band.As the incident angle changed from 40° to 50°,the degree of polarization of seawater increased,and it was higher than that for the oil-sick between wavelengths of 400-1000 nm at an angle of incidence of 50°.This research on the polarized characteristics of an oil-slick on a sea surface brings new scientific techniques to the monitoring of sea-surface pollution by remote sensing.     

Electric field-induced oscillation of sessile droplets

We report a novel oscillatory behavior of a sessile droplet on a hydrophobic surface. The droplet was placed on an electrode with a hydrophobic surface and close to, but not touching, a second needle-like electrode. The change in the contact angle was observed only when the droplet oscillated. In a traditional electro-wetting experiment, however, the contact angle decreased immediately when an alternating current electric field was applied. In addition, the non-contact mode gave rise to a true sessile condition of the droplet, whose oscillation amplitude was not linearly proportional to the driving voltage but reached a maximum value.     

Experimental study on spectral responses of offshore oil slick

Using the seawater taken from Liaodong Bay and crude oil taken from Liaohe Oilfield, a laboratory experiment was designed to study the change of reflectance spectrum of artificial offshore oil slick with its thickness and to identify the spectrum ranges suitable for quantifying the thickness of the oil slick. During the experiment, crude oil was continuously dropped into the seawater to generate artificial oil slick with different thicknesses. After every drop of crude oil was added, reflectance spectrum of the oil slick was measured with a high resolution spectroradiometer （ASD FieldSpec Pro FR）. The influence of oil slick thickness on its reflectance spectrum was explored through statistical analysis. The results show that the reflectance of oil slick changes marginally with oil slick thickness and higher than that of seawater in infrared band from 1150 to 2500 nm. This spectrum range can be practically used to distinguish oil slick from seawater. In the spectrum range from 400 to 1150 nm, the reflectance of oil slick decreases with its thickness. The negative power function is the best-fit function expressing the relationship between the reflectance and thickness. The spectral characteristics of oil slick are very distinct at 550 and 645 nm. They are the best wavelengths for monitoring the existence of offshore oil slick and estimating its thickness.     

Corrosion-wear behavior of nanocrystalline Fe88Si12 alloy in acid and alkaline solutions

The corrosion-wear behavior of a nanocrystalline Fe₈₈Si₁₂ alloy disc coupled with a Si₃N₄ ball was investigated in acid (pH 3) and alkaline (pH 9) aqueous solutions. The dry wear was also measured for reference. The average friction coefficient of Fe₈₈Si₁₂ alloy in the pH 9 solution was approximately 0.2, which was lower than those observed for Fe₈₈Si₁₂ alloy in the pH 3 solution and in the case of dry wear. The fluctuation of the friction coefficient of samples subjected to the pH 9 solution also showed similar characteristics. The wear rate in the pH 9 solution slightly increased with increasing applied load. The wear rate was approximately one order of magnitude less than that in the pH 3 solution and was far lower than that in the case of dry wear, especially at high applied load. The wear traces of Fe₈₈Si₁₂ alloy under different wear conditions were examined and analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results indicated that the tribo-chemical reactions that involve oxidation of the worn surface and hydrolysis of the Si₃N₄ ball in the acid solution were restricted in the pH 9 aqueous solution. Thus, water lubrication can effectively improve the wear resistance of nanocrystalline Fe₈₈Si₁₂ alloy in the pH 9 aqueous solution.     

The distribution of the oil derived from Cambrian source rocks in Lunnan area,the Tarim Basin,China

There are great differences in biomarks between Cambrian oil and Middle-Upper Ordovician oil. In this stuty, the authors analyzed 40 oils found in Lunnan area by GC-MS and calculated the content of Cambrian oil in the 40 oils according to the steroid indexes of typical oil mixture and match experiment. The results show that it is a general phenomenon in Ordovician reservoir that the oil derived from Cambrian source rock mixed with the oil derived from Middle-Upper Ordovician source rock in Lunnan area, the mixture degree of the two oils is lower in Carboniferous reservoir than in Ordovician reservoir, and the oils kept in Triassic reservoir have single source, Middle-Upper Ordovician source rock. The mixture oils mainly composed of Cambrian oil (>50%) distributed in Sangtamu fault zone, and the oils found in Lunnan fault zone are Middle-Upper Ordovician oil. This distribution of oils in Lunnan area is owing to that Lunnan fault zone is located in anticline axis part, Lunnan fault zone underwent serious erosion, and the oils from Cambrian source rock accumulated in Lunnan fault zone were degraded completely during Caledonian-Hercynian movement. But the Cambrian oil accumulated in Sangtamu fault zone was not degraded completely and some of them were left for the location of Sangtamu fault zone is lower than Lunnan fault zone. Later, the oil derived from Middle-Upper Ordovician source rock mixed with the remained Cambrian oil, and the mixture oil formed in Sangtamu fault zone.     

The distribution of the oil derived from Cambrian source rocks in Lunnan area, the Tarim Basin, China

There are great differences in biomarks between Cambrian oil and Middle-Upper Ordovician oil. In this stuty, the authors analyzed 40 oils found in Lunnan area by GC-MS and calculated the content of Cambrian oil in the 40 oils according to the steroid indexes of typical oil mixture and match experiment. The results show that it is a general phenomenon in Ordovician reservoir that the oil derived from Cambrian source rock mixed with the oil derived from Middle-Upper Ordovician source rock in Lunnan area, the mixture degree of the two oils is lower in Carboniferous reservoir than in Ordovician reservoir, and the oils kept in Triassic reservoir have single source, Middle-Upper Ordoviclan source rock. The mixture oils mainly composed of Cambrian oil （〉50%） distributed in Sangtamu fault zone, and the oils found in Lunnan fault zone are Middle-Upper Ordovician oil. This distribution of oils in Lunnan area is owing to that Lunnan fault zone is located in anticline axis part, Lunnan fault zone underwent serious erosion, and the oils from Cambrian source rock accumulated in Lunnan fault zone were degraded completely during Caledonian-Hercynian movement. But the Cambrian oil accumulated in Sangtamu fault zone was not degraded completely and some of them were left for the location of Sangtamu fault zone is lower than Lunnan fault zone. Later, the oil derived from Middle-Upper Ordovician source rock mixed with the remained Cambrian oil, and the mixture oil formed in Sangtamu fault zone.     

Osmotic Pressure of Water in Nafion~

Mechanical failure modes leading to cracks or breeches in proton exchange membrane fuel cells are driven by mechanical forces associated with swelling from water uptake and shrinkage from dehumidifi-cation. To determine the magnitude of compressive mechanical stress imposed by water swelling in a proton exchange fuel-cell membrane, the osmotic pressure of water in a perfluorosulfonic acid ionomer (Nafion? N 117) membrane was measured using a hydrostatic piston-cylinder device with an in-situ hydrophilic frit. Experiments indicate that hydrostatic stresses greater than 103.5 MPa are created in a membrane when swollen with water at 23℃ suggesting that pressure from water swelling can distort Nafion N 117-based structures as the osmotic pressure is of the same order of magnitude as the flow stress of Nafion N 117.     

The Dissolution of the Cellulose in the N - ethylmorpholine - N - oxide (NMMO) - Water System with Hydrothermolysis

Tbe N - methylmorpholine - N - oxide (NMMO) - water solvent was used to dissolve the cellulose that was achieved by means of hydrothermolysis. Sample B, RS and WS used here were made from beech, rice straw and wheat straw respectively. They could be completely dissolved in the NMMO - water system. A commercial a - cellulose was employed in the comparative experiment. The entire dissolving process was Investigated. At a given temperature, the vacuum condition applied to the mixture of the cellulose and NMMO - water was very important in order to accelerate the dissolution of cellulose and shorten the dissolving period. After dissolution, degree of polymerization (DP) of all samples was measured by viscometry. Longer dissolving time and higher temperature could cause the degradation of the dissolved cellulose. N- propyl gallate could prevent the degradation of cellulose during the process of dissolution.     

Distribution and partition of polybrominated diphenyl ethers （PBDEs） in water of the Zhujiang River Estuary

The spatial, temporal, and vertical distributions of polybrominated diphenyl ethers （PBDEs） in water columns from the Zhujiang River Estuary were examined, and the partition behavior of PBDEs between particle and dissolved phases was investigated in the present study. The results show that the distributions of PBDEs concentrations in the water varied with the sampling seasons. The PBDEs concentrations in water samples were lower in May 2005, when the brackish water was dominant in the estuary, than in October 2005, when fresh water from river runoff dominated the estuary. The spatial distribution of PBDEs in October 2005 indicated that the river runoff was the major mode to input PBDEs to the estuary, and the concentration of PBDEs in water might be dissolved organic carbon （DOC） dependence. The spatial and vertical distributions of PBDEs in May 2005 were relatively homogeneous, and SPM was the major factor on controlling the levels of PBDEs in this sampling time. Both DOC and POC could play certain roles in determining the distribution and partition of PBDEs between particle and dissolved phases, but their effects varied with the water properties.     

Oil cracking： An important way for highly efficient generation of gas from marine source rock kitchen

The potentials of gas generation by kerogen in the late period and by crude oil cracking are closely related to the origin of natural gas in the high- to over mature marine area and their exploration perspectives. The carbon structure of kerogens, with different types and at different evolution stages, have been experimentally studied using the high magnetic field solid ^13C nuclear magnetic resonance technique in order to determine the oil and gas potential of kerogens. Results show that the contents of gas potential carbon（GPC） of types Ⅰ, Ⅱ, Ⅲ kerogens at the high- to over mature stage are very low, indicating their weak gas-generating capacity and limited gas production; however, the content of oil potential carbon（OPC） of the low mature type Ⅰ kerogen is much higher, implying that a large amount of crude oil generated during the oil-generating period will be the material for later gas generation by oil cracking. The kinetic experiment of gas generation by crude oil cracking shows that, when the temperature is about 160℃（R0=1.6%）, the crude oil will start to produce large amounts of gas; the temperature range for major gas generation of crude oil is higher than that of the kerogens, and the gas production is 2 to 4 times higher than that of kerogens. The natural gas derived from oil cracking （called oil-cracked gas） is much abundant in methyl hexamethylene, which is quite different from the natural gas produced by thermal degradation of kerogens （named kerogen degradation gas） at high- to over mature stage.     

Effects of Foliage Boron-Spraying on Seed Yields and Fatty Acid Composition of Tree Peony(Paeonia ostii ‘Feng Dan')

The influence of the foliage boron(B)-spaying concentration on the yield and fatty acid composition of tree peony(Paeonia ostii ‘Feng Dan') was explored in the experiment of 2014-2015. In this research, a statistically significant correlation was found between the mass concentration of foliage boron-spraying and tree peony seed yield. Maximum yield increment of tree peony seeds was obtained when the boron-spraying concentration was 4 g/L. The composition of fatty acid was analyzed by gas chromatography-mass spectrometry(GC-MS), and the main components of the fatty acid composition were quantified by internal standard method. The increase in the oil extraction rate after foliage boron-spraying nutrition of different concentration was significant and ranged between 0.04% and 11.43%. Seed oil production and oil extraction rate were also increased due to the increase of seed yields. Furthermore, foliage boron-spraying had a significant effect on the content of linolenic acid and linoleic acid in seed oil.     

Experimental evidence for formation water promoting crude oil cracking to gas

Crude oil cracking to gas is the key to determining the exploration potential and strategy for deep hydrocarbon resources.Identifying the factors that affect the threshold and potential of crude oil cracking to gas as well as other possible influencing factors will provide the scientific basis for deep hydrocarbon exploration.A comparison of pyrolysis simulation experiments of crude oil,hydrous crude oil,and various water media under a constant temperature(350℃) and pressure(50 MPa) shows that water plays a large role in crude oil cracking to gas.(1) When water is added,the gas yields increase significantly,including those of alkane gases and non-hydrocarbon gases:the yield of alkane gases increases 1.8-3 times;the yields of H2 and CO2 also increase significantly.This means that water takes part in the process of crude oil cracking to gas,and supplies hydrogen.Therefore,the presence of water will dramatically enhance the potential of crude oil cracking to gas.(2) Mg2+ ions in the formation water promote the crude oil + water reaction to some extent and increase the total yield of alkane gases and the yields of both H2 and CO2 ;more interestingly,the i-C4/n-C4 and i-C5/n-C5 ratios increase significantly.This indicates that Mg2+ ions in formation water act as a catalyst,and a disproportionation reaction is involved in the crude oil + water reaction.This study helps us to understand the factors influencing crude oil cracked gas and to evaluate the hydrocarbon resources in deep sedimentary basins.     

Wear behavior of bainite ductile cast iron under impact load

The dry impact wear behavior of bainite ductile cast iron was evaluated under three different impact loads for 30000 cycles. The strain-hardening effects beneath the contact surfaces were analyzed according to the surfaces’ micro-hardness profiles. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to observe the worn surfaces. The results indicated that the material with the highest hardness was the one continuously cooled at 20°C, which exhibited the lowest wear rate under each set of test conditions. The hardness of the worn surface and the thickness of the hardened layer increased with the increases in impact load and in the number of test cycles. The better wear performance of the sample cooled at 20°C is attributed to its finer microstructure and superior mechanical properties. All the samples underwent the transformation induced plasticity (TRIP) phenomenon after impact wear, as revealed by the fact that small amounts of retained austenite were detected by XRD.     

Surface properties of superfine alumina trihydrate after surface modification with stearic acid

The surface properties of superfine alumina trihydrate (ATH) after surface modification were studied by measuring the contact angle, active ratio, oil adsorption, total organic carbon, adsorption ratio, and Fourier transform infrared (FTIR) spectrum. The contact angle increased initially and then slowly decreased with an increase of the amount of stearic acid. However, the surface free energy decreased initially and then increased. Surface modification with stearic acid or sodium stearate can benefit from elevating temperature. The base surface tension component and the free energy of Lewis acid-base both declined sharply following the surface modification. Excess stearic acid was physically adsorbed in the form of multilayer adsorption, and an interaction between oxygen on the ATH surface and hydroxyl in stearic acid was subsequently determined. Our results further indicated that the contact angle and adsorption ratio can be used as control indicators for surface modification compared with active ratio, oil adsorption and total organic carbon.     

Determination of Dimethylallylamine by Titration in Nonaqueous Solvent

The content of dimethylallylamine was determined using glacial acetic acid as solvent, acetic-formic mixture as an anhydrite, perchloric acid-glacial acetic acid as titrant, and 1% crystal violet in acetic acid as indicator in the presence of methylamine and dimethylamine The influences of inert constituents and water on the titration were investigated, and a complete analytical method was determined. The results showed that the determination error of total amines increased with water increasing, while the effect of water on the determination of dimethylallylamine was little when the amount of water was within 5%, the relative error was generally within 1%, and that the end-point was acutely when about 10% chloroform was added. Compared with gas chromatography, this method is simple, convenient and accurate.     

Preparation of pH-responsive ceramic composite membranes by grafting acrylic acid onto α-alumina membranes

A pH-responsive ceramic composite membrane was prepared by chemical graft polymerization of acrylic acid （AA） onto the KH-570 modified （x-alumina membrane. The influence of monomer concentration on the gating characteristics of the pH-responsive membrane was investigated. The FT-IR spectrum, contact angle and water filtration rate of the membrane were measured. The monomer concentration was found to have a remarkable effect on the pH-response coefficient and the water filtration rate. In addition, the grafted membrane exhibited fast and reversible response to the pH change in the external solution.     

Role of acetylcholine on plant root-shoot signal transduction

The role of accetylcholine (ACh) on plant root-shoot communication was investigated using the root-split system of Vicia faba L.In the experiments,slight osmotic stress caused the decrease of ACh content in root tips and the xylem sap transported up per time unit from root tip to the shool when the water potential of the shoot was kept unchanged .It also caused the decrease of ACh content in the abaxial epidermis,The decrease was highly correlative to the changes of transpiration rate,suggesting that the decrase of ACh content probably functions as a signal to regulate stomatal behavior,The effect of osmotic stress might be mainly through the inhibition of the ACh synthesis in root tip ;thus further influences the ACh content in root tip ,xylem sap and abaxial epidermis and resulting in the changes of stomata behavior,These results provide new evdence that plants transduce positive and negative signals among roots and shoot to coordinate stomatal behavior and adapt to variable environments.     

Shear-thickening behavior of Fe-ZSM5 zeolite slurry and its removal with alumina/boehmites

A cryogenic scanning electron microscopy (cryo-SEM) technique was used to explore the shear-thickening behavior of Fe-ZSM5 zeolite pastes and to discover its underlying mechanism. Bare Fe-ZSM5 zeolite samples were found to contain agglomerations, which may break the flow of the pastes and cause shear-thickening behaviors. However, the shear-thickening behaviors can be eliminated by the addition of halloysite and various boehmites because of improved particle packing. Furthermore, compared with pure Fe-ZSM5 zeolite samples and its composite samples with halloysite, the samples with boehmite (Pural SB or Disperal) additions exhibited network structures in their cryo-SEM images; these structures could facilitate the storage and release of flow water, smooth paste flow, and avoid shear-thickening. By contrast, another boehmite (Versal 250) formed agglomerations rather than network structures after being added to the Fe-ZSM5 zeolite paste and resulted in shear-thickening behavior. Consequently, the results suggest that these network structures play key roles in eliminating the shear-thickening behavior.     

Multi-factor sensitivity analysis of shallow unsaturated clay slope stability

An unsaturated clay slope, with various sloping angles and a thickness of 14 m, consists of backfill, slope soil and residual soil. Slide interfaces were determined by geophysical approaches and the original slope was reconstructed. Sub-slope masses were classified based on the varieties of sloping angle. A force recursive principle was proposed to calculate the stability coefficient of the sub-slope masses. The influencing factors such as sloping angle, water content, hydrostatic pressure, seismic force as well as train load were analyzed. The range and correlation of the above-mentioned factors were discussed and coupled wave equations were established to reflect the relationships between unit weight, cohesion, internal frictional angle, and water content, as well as between internal frictional angle and cohesion. The sensitivity analysis of slope stability was carried out and susceptive factors were determined when the factors were taken as independent and dependent variables respectively. The results show that sloping angle, water content and earthquake are the principal susceptive factors influencing slope stability. The impact of hydrostatic pressure on slope stability is similar to the seismic force in quantity. Train load plays a small role in slope stability and its influencing only reaches the roadbed and its neighboring slope segment. If the factors are taken as independent variables, the influencing extent of water content and cohesion on slope stability can be weakened and train load can be magnified.