Search

Protein crosslinking plays an important role in cereal food processing. In recent years, many studies have been carried out on the crosslinking of cereal proteins. However, it is not clear about the principles and molecular mechanisms of crosslinking of cereal proteins. In this review, three kinds of different methods, including physical cross-linking, chemical cross-linking and enzymatic cross-linking, for enhancing the crosslinking of cereal proteins in cereal food processing were summarized, and their recent advances were discussed. Moreover, the effects of the three kinds of protein crosslinking methods on the structural properties of cereal proteins and related products were analyzed. Finally, the possible problems in these three kinds of protein crosslinking methods were discussed and prospected.

Objective To report a case of subdural hematoma (SDH) puncture and drainage combined with epidural blood patch (EBP) in the treatment of spontaneous intracranial hypotension (SIH) complicated with SDH and venous cerebral infarction, and summarize the diagnostic and treatment ideas. Methods and Results A male patient presented with sudden headache accompanied by hemiplegia, the headache was relieved in recumbent position and aggravated when standing or sitting for a long time. He was initially diagnosed as acute cerebral infarction before hospitalization and was given rt⁃PA intravenous thrombolysis. And then was diagnosed as cerebral venous thrombosis (CVT), which was treated through dehydration and anticoagulation, during which bilateral SDH occurred and progressive aggravated, and sent to Department of Emergency of Xuanwu Hospital, Capital Medical University. He was diagnosed as bilateral frontotemporal parietal SDH and effusion, CVT with venous cerebral infarction, and SIH. Soft channel twist drill craniotomy was performed firstly, then targeted autologous EBP were performed when the condition came to steady. The patients' symptoms improved, and residual SDH absorbed gradually. Conclusions For CVT patients accompanied by focal nerve dysfunction and SDH showed postural headache, the possibility of SIH could be considered, and stereotactic soft channel SDH puncture and drainage combined with targeted autologous EBP can play a curative effect.

Carbonate cements formed at different stages in sandstone have different mineral compositions, structural characteristics and carbon and oxygen isotope compositions. Carbon stable isotope compositions in cements can be used to indicate the source of carbon in diagenetic fluids, while oxygen stable isotope can be used to estimate the temperature and the source of fluid at the time of crystallization. In order to obtain the carbon and oxygen isotope compositions of different kinds of carbonates in sandstone cements, off-line selective acid extraction method was usually used to extract and test the carbon and oxygen isotope compositions of each carbonate. In order to overcome the shortcomings of the off-line method such as cumbersome process and low efficiency, the temperature and time experiments of the reaction of the mixture sample with 100% phosphoric acid were carried out for the first time by using Gasbench-IRMS with different ratios of quartz, calcite and dolomite mixture samples in this study. When the particle size of the sample is mainly about 63-75 μm, the reaction temperature is 25 ℃ and the reaction time is 2 h, the generated CO2 represents the carbon and oxygen isotopic compositions of calcite. When the reaction temperature is 25 ℃, there is almost no CO2 generated in reaction of dolomite with 100% phosphoric acid for 1 h, and the yield of CO2 is only about 3% for 2 h. The mixture experiment showed that this method is only suitable for the mixture samples with more calcite than dolomite. When the content of calcite is higher than that of dolomite, Gasbench-IRMS can be used to separate calcite and dolomite mixture samples online, and test C and O isotope compositions. The carbon dioxide produced at 25 ℃ for 2 h represents the C and O isotope compositions of calcite. The CO2 gas is removed after another 2 h of reaction, then the carbon dioxide produced at 50 ℃ for 18 h represents δ13C and δ18O of dolomite. The precision of δ13C and δ18O is better than 0.15‰ (1σ) and 0.20‰ (1σ), respectively.

The significant changes enabled by the fog computing had demonstrated that Internet of Things (IoT) urgently needs more evolutional reforms. Limited by the inflexible design philosophy; the traditional structure of a network is hard to meet the latest demands. However, Information-Centric Networking (ICN) is a promising option to bridge and cover these enormous gaps. In this paper, a Smart Collaborative Caching (SCC) scheme is established by leveraging high-level ICN principles for IoT within fog computing paradigm. The proposed solution is supposed to be utilized in resource pooling, content storing, node locating and other related situations. By investigating the available characteristics of ICN, some challenges of such combination are reviewed in depth. The details of building SCC, including basic model and advanced algorithms, are presented based on theoretical analysis and simplified examples. The validation focuses on two typical scenarios: simple status inquiry and complex content sharing. The number of clusters, packet loss probability and other parameters are also considered. The analytical results demonstrate that the performance of our scheme, regarding total packet number and average transmission latency, can outperform that of the original ones. We expect that the SCC will contribute an efficient solution to the related studies.

BACKGROUND The measurement of 40Ar content in K-Ar dilution method includes sample melting and releasing gas, gas purification and enrichment, mass spectrometry measurement. With the application of a newly designed double vacuum furnace and gas purification system, the experiment process gradually changes from manual operation to automatic program control, but the parameters are unclear. OBJECTIVES To determine the parameters by conditional experiments and establish a complete measurement method of 40Ar content in K-Ar dilution method. METHODS Parameters were determined by releasing and absorbing an air standard in activated carbon cold finger with different times, melting different types of samples with different temperatures of the double vacuum furnace. The method reliability was verified by K-Ar dating for SK01 sanidine standard. RESULTS The optimal heating release time for activated carbon cold finger was 500s, and the adsorption time was 200s. Using these conditions, the gas produced by the melting in the furnace can be completely transferred and released to avoid isotope fractionation. The corresponding melting temperature was used for different types of samples to ensure that the samples were completely melted and outgassed, the melting temperature of the furnace for clay minerals, biotite, and muscovite should be set to 1400℃, and 1500℃ for amphibole, 1550℃ for basic rock, and 1600℃for potassium feldspar. The K-Ar dating of 10 sets of SK01 sanidine standards showed that the results were consistent with 40Ar-39Ar dating ages. CONCLUSIONS The obtained condition parameters meet the accurate measurement of 40Ar content using the K-Ar dilution method.

C19H25N5O, monoclinic, P21 (no. 4), a = 16.0600(2) Å, b = 5.3992(1) Å, c = 19.8514(2) Å, β = 94.260(1)°, V = 1716.58(4) Å3, Z = 4, Rgt (F) = 0.0350, wRref(F2) = 0.0908, T = 100.00(10) K.

BACKGROUND The oxygen isotopic composition of sulfate radical in mineral or water can be used to identify the source and transformation process. At present, the common method is to convert sulfate radical into barium sulfate and the oxygen isotopic composition determined offline or online. It is possible to shorten the working life of the furnace when δ18O of barium sulfate is measured online under 1420℃. The reaction temperature can be reduced by adding reductant carbon, but there is less discussion about the reaction temperature reported. OBJECTIVES To confirm the key technical parameters during determination of oxygen isotope composition in barium sulfate online. METHODS Nickel-plated carbon was added in a series of conditional experiments during determination of oxygen isotope composition of barium sulfate by elemental analysis/isotope ratio mass spectrometry (EA-IRMS). RESULTS 1350℃ was chosen as the online pyrolysis temperature of barium sulfate by adding Ni-C. The sample size ratio between Ni-C and BaSO4 was set as 0.73-2.15. The sample weight of Ni-C and BaSO4 was 700±100μg, respectively. Under the above conditions, the precision of δ18O of BaSO4 measured by EA/HT-IRMS was ±0.12‰-±0.26‰, better than the reported results of ±0.20‰-±0.50‰. CONCLUSIONS On the premise of better precision, the online pyrolysis temperature of barium sulfate can be reduced to 1350℃ and the lifetime of the reactor can be improved by adding Ni-C.

BACKGROUND Reagent purification, sample pretreatment, environmental humidity, reactor cleanliness and experimental quality control are the main influence factors for determination of oxygen isotopic composition of silicates and oxide minerals by BrF5 method. OBJECTIVES To determine the optimal experimental conditions and improve the accuracy by selecting silicates and oxide minerals as laboratory raw materials for oxygen isotopic composition analysis. To discuss the influence factors for determination of oxygen isotopic composition of silicates and oxide minerals by BrF5 method. METHODS Using BrF5 analysis method and taking standard sample as the reference, oxygen isotopic compositions of silicates and oxide minerals were determined at different calcination temperatures. At the same time, the effects of environmental humidity and reactor cleanliness on the analytical results were also studied. RESULTS The results show that 650-750℃ is the best calcination temperature range for removing carbon components during oxygen isotope analysis, which can avoid the isotope fractionation caused by temperature. By reducing the relative environment humidity or the sample loading time within 0.5min, the lower δ18O values caused by vapor was improved. The new reactor, or the reactor with large yellow substance falling off, or the contaminated reactor will reduce the yield of oxygen and cause oxygen isotope fractionation, so the reactors should be fluorinated or purged in time. The sample and standard material is loaded alternately for each reactor to monitor the reliability of the isotopic composition of the sample. The results of oxygen isotopic composition of GBW04409 are consistent with the recommended values. The relative standard deviation is better than 0.1‰ for δ18O under the optimized conditions. CONCLUSIONS The proposed method can effectively control oxygen isotope fractionation and improve the applicability of BrF5 oxygen isotope analysis method.

Accurate measurement of Argon isotopes is the premise of Ar-Ar dating with high precision. Two main kinds of instruments for Ar isotope measurement are Single-collector and Multi-collector Mass Spectrometers, among which the Multi-collector Noble Gas Mass Spectrometer can produce data with better accuracy and reproducibility. Some main factors affecting the accuracy and reproducibility of the results during the measurement of the Ar isotopes by the Argus Multi-collector Noble Gas Mass Spectrometer are discussed in this paper. Results show that the background of the whole system in static mode is very low and has little effect on the measurement of Ar isotope composition. The efficiency of the multiplier of the instrument is better than 99.67%, which can improve the measurement precision of low Ar samples. When the signal of 40Ar is less than 0.5 V, the standard error is only 0.11% for the 40Ar/36Ar ratios measured by the CDD, while the standard error is 0.53% when the ratios are measured using a Faraday cup. The mass discrimination effect of the instrument could be calibrated with the logarithmic law through the repeated measurement of argon isotopes in air and the relative standard error of the mass discrimination is only 0.0434%. Using the example of the determination of argon isotopes in air, it can be demonstrated that the efficiency of the measurement by Argus Multi-collector Mass Spectrometer is higher than that of the Single-collector Mass Spectrometer with higher precision and accuracy. Therefore, the Multi-collector Mass Spectrometer is highly suitable for the high-precision Ar-Ar dating of young and potasium-poor samples.

When there are water rich-karst caves or large faults in front of the tunnel face, blind construction may easily cause safety accidents such as water inrush, mud outburst and collapse. Using advanced geological prediction methods to predict the spatial distribution of unfavorable geological bodies can greatly reduce construction risks. This paper introduces a new seismic reflection imaging system TSP-SK, and discusses the features, working mode and data processing methods of the prediction system, and verifies the reliability of TSP-SK through practical tunnel engineering prediction case. The result shows that TSP-SK can collect high signal-to-noise ratio seismic reflection data with little interference from clean first arrival when the water sealing effect of explosives in the borehole is good. Good reflection wave pickup effect can be obtained when the maximum gain of inverse Q filter and Q value are taken in the range of 15 to 30. The prediction results of TSP-SK are in good agreement with the actual excavation results, that is, the areas with low P-wave velocity indicate poor rock mass quality, and the area of low S-wave velocity is more likely to produce water from construction.

We introduce a new tunnel long distance prediction seismic reflection imaging system called TETSP. We use TETSP and the latest generation TSP303 to advance geological comparison detection in Zhangcun tunnel in Thousand Island Lake-Hangzhou water transfer project. Firstly, we introduce the layout of TETSP observation system and data processing flow. Secondly, we expound the differences between TETSP and TSP303 in aspect of geophone coupling and acoustic interference suppression. Lastly, we analyze the characteristics of reflection anomalies in the karst cave zone of the rock mass. The actual tunnel excavation results verify the reliability of the TSP303 and TETSP prediction. Several conclusions are drawn as follow. Firstly, two kinds of seismic reflection technology both can detect whose wave impedance interface exist significant difference in front of tunnel face, but the TSP303 is more accurate. Secondly, the poor integrity of the rock mass is corresponding to the low velocity of P-wave and S-wave.

In order to solve problems of low efficiency of locomotive transportation and indefinite materials route caused by shortage of efficient monitoring and control methods of track locomotive transportation system of Chengzhuang Coal Mine, the paper pointed out necessity of designing management system of underground materials transportation. It analyzed advantages and disadvantages of active RFID technology and passive RFID technology with high-frequency, and proposed a management system of underground materials transportation based on UHF RFID. The system is composed of passive RFID label of anti-metal, fixed-mode UHF FRID reader-writer, handed-mode FRID reader-writer and management software of material transportation, and can realize functions of distinguishing, location and remote monitoring for underground locomotives and materials. The actual application showed that the system can improve efficiency of mine auxiliary haulage system effectively.