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Metal–organic frameworks (MOFs) with zeolitic structure process fantastic structural metrics and display excellent applications in many aspects; however, they are difficult to assemble. Herein, on the basis of a tetrahedral Zn4O cluster and a 3,5-bis(2,4-dicarboxylphenyl)nitrobenzene (H4L) ligand, a novel sodalite (SOD) zeolitic cluster framework (ZCF), {[Zn4(O)(L)2]·4DMF·6H2O}n(ZCF-1; DMF = N,N-dimethylformamide), has been hydrothermally synthesized. Compared with the traditional SOD zeolitic framework of ZIF-8, the cage size of ZCF-1is dramatically improved from 16.9 to 29.2 Å by the introduction of longer tetradentate carboxylic ligands. Moreover, because of the functional nitryl group in the ligand, ZCF-1exhibits a high CO2/CH4selectivity. Hence, further research on the chemical fixation of CO2is implemented, which reveals excellent heterogeneous catalytic activity and durability. Especially, a unique selective catalytic performance with a high yield of 88.3% on a larger molecular size reactant (glycidyl phenyl ether) is observed, which is attributed to the stereoselection effect of the superlarge cage and abundant Zn4O catalytic clusters in ZCF-1.

To establish a simple method to separate and purify the magnesium lignosulfonate from the red liquor, the properties of the alkali precipitation of magnesium lignosulfonate in the red liquor were investigated. The results show that the magnesium lignosulfonate could be precipitated by alkali from red liquor. The maximum amount of precipitation occurs when pH value was 13. The precipitation of the red liquor of acid magnesium sulfite is caused by magnesium. It was different from sodium lignosulfonate of the red liquor of acid sodium sulfite. The repeated alkaline precipitation after acid soluble method could be isolated and purified lignosulfonate magnesium effectively at some extent.

The paper discusess mainly how to accurately measure the real-time length of fiber optic gyroscope sensing coil (fiber coil) in the process of FOG coil winding. First, using the improved moving target detection algorithm to process the fiber images collected by machine vision. Secondly, using software algorithm to calculate the real-time radius of fiber winding. Finaly, combining the incremental optical encoder with real-time radius to calculate real-time winding length of fiber coil.

FOG coil (fiber coil) is the core component of the FOG. During the winding, the tension of fiber winding directly affects the performance of fiber coil. The paper proposes a PID controller as the core of the tension control method and establishes the related model between rolling-up fiber spool and discharging fiber spool. The simulation results in Matlab Simulink show that the tension control system can primely coordinate the winding tension and have fast response, small overshoot, high accuracy and stability.

To improve the accuracy of the transient temperature detection system, Transient temperature inversion processing algorithms is proposed based on spectrum analysis of speckle pattern interferometry. The interference fringes is formed by speckle interferometry in the system, and due to transient temperature changes cause the material strain, so that the speckle interference pattern changes. the interference fringes on the measured surface is obtained by the area array CCD collection before and after deformation. The corresponding spectrum density function will changes by the changes of transient temperature, and the amplitude changes of center wavelength is inverted by the speckle pattern interferometry. Through detecting and calculating the ratio of the amplitude of the center wavelength, the transient temperature can be obtained by spectrum analysis. In the analysis and calculation for the function of transient temperature and material strain, material strain and interference fringes, derived the amplitude and phase function of the transient temperature change and interference fringes, so as to provide the necessary conditions for detecting the use of spectral density function temperature. Experiment using 660nm laser diode, SI6600 type area CCD detector to obtain the speckle pattern interference fringes, system extracts the amplitude ratio of the central wavelength from spectral distribution function, and by calculation and calibration the detection accuracy of temperature can be achieved of 2℃. Compared to traditional methods that is direct detection for interference fringes changes, the new methods improve the accuracy by nearly an order of magnitude. It is more accurate detection and better uniformity, better stability.

Removing the carbohydrate of black liquor through biological treatment to converted it into alcohol, as to improve the purity of lignin. Through the study we found that the content of lignin and carbohydrate decreased in the biological purification process. The content of lignin in alkaline black liquor decreases 12.9% after fermentation. And in alkaline sodium sulfite black liquor it decreases 6.4%. Compared with black liquor, the content of total sugar in soda black liquor decreased 77.1%. And in alkaline sodium sulfite it decreases 77.8%. The lignin purity of two kinds of black liquor will improve after the biological treatment. Lignin of alkaline black liquor by biological treatment and organic matter of black liquor ratio increase 28.74%, which increases 29.35% in alkaline sodium sulfite black liquor. The viscosity and CODcr of two kinds of black liquor will reduce after the biological treatment. The relative viscosity of alkaline black liquor after enzymolysis reduces to 1.178, while the relative viscosity of alkaline sodium sulfite black liquor reduces to1.164. The CODcr of alkali black liquor after biological treatment decreases 15.65%; and the CODcr of alkaline sodium sulfite liquor reduces 10.59%.

For a large-scale industrial separations and purifications of the lignin in the alkaline pulping, we use aluminum chloride as a catalyst to heat the alkaline pulping black liquor, in order to discuss effects in the nature of high temperature heat treatment process in the alkaline pulping black liquor and aluminum chloride on the nature of alkaline pulping black liquor. The results show that temperature increased and the lignin and carbohydrate content increased and the solids content and pH decreased in the high temperature heat treatment process. When joining the catalyst aluminum chloride, lignin, carbohydrates, solids content and pH value were increased, and increased with increasing amount of aluminum chloride. It proves that the Aluminum chloride plays a big role in the process of the alkaline pulping black liquor heat treatment. It will provide some theoretical basis of the heat treatment of alkaline pulping black liquor.

In alkaline conditions, magnesium salt of red liquor will produce precipitation phenomenon and generate colloidal substances. The sediment was mainly lignin sulfonate. In order to extract and separate the lignin sulfonate of red liquid, when the pH of red liquid adjusted to different pH with different alkaline solution, study on its relation to pH and the amount of alkali and precipitation, discuss the relationship to the content of precipitation lignin in red liquid, the viscosity of upper liquid after centrifugation and temperature as well. Adjusting the pH values of red liquid to 13 with NaOH, adjusting it to 12 with KOH, then adjusting its pH to 13 and adding 20 mL Ca(NO3)2. We got that the last kind of condition generate the biggest quantity of precipitation. The changes of temperature and the amount of calcium nitrate can also affect the formation of precipitation, under the optimal conditions of pH, each group of experiments got the largest amount of precipitation at 40 ℃; The amount of precipitation increased following the increasing of calcium nitrate content; Ash content increased following the increasing of precipitation content.

The black liquor contains a large amount of suspended solids, organic pollutants and toxic substances, the black liquor discharged directly into water bodies will lead to serious pollution. So we regards the alkaline pulping black liquor as a research object, using autoclave to heat the mixture of aluminum chloride and soda black liquor lignin. By changing the heating temperature and the pH before the heat treatment, we analyze the lignin and carbohydrates in the cooking liquid to study cleavage situation and the corresponding structural changes. The results show that the lignin content accompanied the increase in temperature, organic matter content decreased and part of the decomposition of organic matter. Without adjusting pH, the lignin content is small and ash (inorganic) content is higher.

We treat black liquor using Aspergillus niger to extract lignin and to improve the utilization value of pulping black liquor. Results show that: The original black liquor directly to the biological treatment by Aspergillus niger, biological bacteria cannot grow, when reaction liquid pH ≤ 9; Inorganic salt concentration ≤7% (mass ratio); The black liquor load ratio is 20% (mass ratio), the condition of Aspergillus niger growth is good, the ability to produce acid is strong. After treatment of Aspergillus niger, liquid pH decreased to 3, Aspergillus niger changes settling performance of lignin, and it’s good for extraction and purification of lignin. Lignin methoxyl content reduced 2.81%, alcoholic hydroxyl content reduced 0.31%, and carboxyl content increased 0.15%.

The lignin will drag interference in the system of the sugar determination. Dual wavelength spectrophotometry can remove the interference when making use of the DNS to detect the reducing sugar content in the black liquor. After the analysis to the absorbency graphs of the lignin and the glucose dissolved in the DNS solution at specific wave length region in the ultraviolet-visible light, and the contrast between the coefficients of the relation curves between their absorbency and their concentration at specific wave length, the test wave length is intended to be 520 and 570nm. From the relation curves between the absorbency of the lignin and its concentration at 520nm and 570nm, the magnification coefficient of the differential signal were defined as K2=5.338, K1=3.288.The correction index k=1.2. Then the concentration c (g/L) of the glucose solution can be figured out through formula c=(S/k-0.0165)×M/0.821.Then a group of glucose solution with same glucose addition but different lignin addition had been measured. So this method is effective to detect the reducing sugar content in the black liquor.

The aero load simulator is a typical application of electric dynamic load simulator in the engineering. It is important half hardware-in-loop simulation equipment, which is often used to simulate the aerodynamic torque load on the missile rudder or elevon actuators in the flight. The mathematical model of the electric dynamic load simulator is built using the physical modeling method. The influence of the rudder performance on the model was considered, and modeled it as the disturbance channel in the model. The electric dynamic load simulator is a typical coupled system. Under the different simplification, the validity of the model is verified by the actual experiment.

Aiming at the superfluous force existing in the electric load simulator which can influence the load precision, the text researches the method to improve the control performance of the load system. The work principle of the electric load simulator was introduced, and building the control model of the load system based on, the whole electric load simulator control model was built. It designs feed forward compensation control algorithm. The simulation results proved that the method can solve the interference problem caused by superfluous force in theoretically.

Corn stalk was divided into fractions by morphological characters, and the enzymatic hydrolysis of these fractions was investigated. Chemical composition and the proportions of cells of different compositions were very variable in different morphological structure fractions. This has a fundamental effect on the enzyme adsorption capability and hydrolysis performance. Cellulase, β-glucanase and xylanase were added to the husks, leaves, pith and whole stalks of cornstalks. The results of enzymatic hydrolysis of different morphological structure fractions of corn stalk were compared. It can be seen that the content of sugar degraded by β-glucanase is the highest. The fastest hydrolytic rate and the highest sugar content were obtained in the pith of corn stalks.

A powerful chiral building block: A concise enantioselective synthesis of the diazatricyclic core of sarain A has been accomplished. The novel strategy relies upon the versatile chiral building block (R)‐1(see scheme), and features a tandem Horner–Wadsworth–Emmons–aza‐Michael reaction, an intramolecular Michael reaction, and the diastereoconvergent formation of the third ring. Diazatricyclic core 2possesses all of the necessary functionality for further elaboration into sarain A.

Fe3O4 nanoparticles were simply prepared by a wet chemical solution method. In this method, poly (N-vinyl-2-pyrrolidone) (PVP) was used as surface modified reagent to control the shape of the product. Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD) were used to characterize the asprepared Fe3O4 nanoparticles. Furthermore, the magnetic properties of the sample were investigated by a VSM (vibrating sample magnetometer) technique.

A general and efficient BiCl3-catalyzed substitution reaction of propargylic alcohols with carbon and heteroatom-centered nucleophiles such as allyl trimethylsilane, alcohols, aromatic compounds, thiols and amides, leading to the construction of C–C, C–O, C–S and C–N bonds, has been developed.

A fast, highly efficient, general procedure under microwave irradiation, using silica gel-supported reagents for the synthesis of α-aminophosphonates is developed through a one-pot reaction of aldehydes and ketones with amines.

The reaction of aliphatic N‐tosyl and N‐nosyl imines with arylboronic acids is catalyzed by Rh‐dimer complexes (I) to afford the products with nearly complete enantioselectivities.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access the actual ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.