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Twin-field quantum key distribution (TF-QKD) promises ultra-long secure key distribution which surpasses the rate distance limit and can reduce the number of the trusted nodes in long-haul quantum network. Tremendous efforts have been made towards implementation of TF-QKD, among which, the secure key with finite size analysis can distribute more than 500 km in the lab and in the field. Here, we demonstrate the sending-or-not-sending TF-QKD experimentally, achieving a secure key distribution with finite size analysis over 658 km ultra-low-loss optical fiber, improve the secure distance record by around 100 km. Meanwhile, in a TF-QKD system, any phase fluctuation due to temperature variation and ambient variation during the channel must be recorded and compensated, and all these phase information can then be utilized to sense the channel vibration perturbations. With our QKD system, we recovered the external vibrational perturbations on the fiber generated by an artificial vibroseis and successfully located the perturbation position with a resolution better than 1 km. Our results not only set a new distance record of QKD, but also demonstrate that the redundant information of TF-QKD can be used for remote sensing of the channel vibration, which can find applications in earthquake detection and landslide monitoring besides secure communication., 20 pages, 4 figures and 1 table

Acupoint selection rules of neurogenic dysphagia treated with acupuncture and moxibustion from pre-Qin to late Qing Dynasty in

Vibrationally resolved photoemission spectra of the electronic-state transitions C

To systematically evaluate the clinical efficacy of acupuncture for dysarthria, and to explore the rules of acupoints selection for dysarthria.The clinical randomized control trial literature regarding acupuncture for dysarthria published before January of 2018 were searched in databases, including CNKI, Wanfang, VIP, CBM, PubMed, Ebsco, Science Direct and Cochrane Library. The information of included studies was extract and the quality was assessed. The Meta analysis was performed by using RevMan 5.3 software. The frequency of acupoints was calculated by using Excel software to analyzed the rules of acupoints selection.Totally 21 papers were included, involving 1651 patients. The pooled effects of clinical efficacy: heterogeneity testThe clinical efficacy of acupuncture combined with speech training/regular treatment is significantly superior to that of control group (speech training, medication, regular treatment); acupuncture is safe and effective for dysarthria; the majority of selected acupoint is local acupoints around tongue, throat and neck, as well as extra points and empirical points. However, high-quality randomized controlled trials with large sample sizes are still needed to provide further evidence.

It is necessary to clarify the influence of thermal history on the conversion of aluminate species in sodium aluminate solution in order to optimize Bayer alumina production. The interconversion of various solution species in the systems was investigated by measuring the infrared spectra of sodium aluminate solution with different compositions after separate heat treatment, dilution and concentration. The results show that increasing temperature or prolonging holding time favors the transformation of Al2O(OH)6 2− to Al—OH vibration (condensed AlO4 tetrahedral aluminate ion) at about 880 cm −1 and Al(OH)4 − . A12O(OH)6 2− and Al—OH tetrahedral dimer ions convert rapidly to Al(OH)4 − during the dilution process; however, the back transformation of Al(OH)4 − to the Al—OH tetrahedral dimer ions can occur in diluted sodium aluminate solution. As for the concentration process, the transformation of Al(OH)4 − to A12O(OH)6 2− and Al—OH tetrahedral dimer ions can take place, while it is relatively difficult to

The residual oil in situ microbial gasification technology is a new method to extend the life of oil reservoir, which means using the microbial to transform petroleum hydrocarbons into methane under anaerobic conditions, then the oil reservoir can be exploited or stored in situ. 50ml samples were added to 120ml sterile anaerobic bottle, at the same time, residual oxygen was removed under a gentle stream of high purity nitrogen by Hungate, then the bottle was filled tightly with rubber stoppers to remain strictly anaerobic state. These samples were placed in the incubator in dark condition. 100 days later, methane was detected by gas chromatography analyzing headspace gas, so it is used as inoculum for enrichment culture. 5ml inoculum above mentioned was added to the oil reservoir conditions simulated reactors. The ones with 10ml crude oil sample is (Y), the ones without crude oil sample is (N), at the same time, 10ml inorganic salt culture medium was added to each reactor.

The vulnerability of chemical plants’ disaster bodies was put forward through analyzing the four aspects of disaster bodies’ vulnerability. The impacted factors were analyzed and people, facilities, materials, environment and other targets’ exposure, sensibility, coping ability, resilience were also analyzed, so as to present the index system of chemical plants’ disaster bodies. Therefore, it can give a good idea and method to establish the chemical plants’ overall vulnerability.

Based on the theories of the method of the finite element and the interaction between beam and rail, the common railway bridge: the continuous girder bridge and the simply supported girder bridge as an example, set up the integration of the calculation model of the line-bridge-pier on the continuous welded railway bridge, through the calculation software of Bridge Continuously Welded Rail (BCWR2010), the regular pattern of the effect of the bending force and the regular pattern of the longitudinal displacement distribution of the rail and bridge are analyzed.

Heavy oil Anaerobic degradation by microbial had important theoretical significance and application value of reservoir residual oil biological gasification. The microbial consortium SLY-1 which was enriched from heavy oil reservoir in Shengli oilfield had been cultured at 55°C. DGGE showed that there were two isolated strains which were Anaeromyxobacter sp. and Anaerobaculum sp. respectively and three uncultured bacteria included in SLY-1. After 380d’s culture, SLY-1 had been produced 1006 μmol of methane accounting for 95.2% and 4.8% of other gases (butane, pentane, 2,2-two methyl butane hydrocarbon, 2-cyclopentane etc.). The rate of heavy oil degradation by microbial consortium SLY-1 reached 30.6%. The high viscous microbial consortium could lay the foundation for the residual low-grade heavy oil gasification.

Pentachlorophenol (PCP), a kind of ionizable hydrophobic organic contaminant, had been extensively used in agricultural, industrial, and domestic applications as an important component of fungicides, bactericides, herbicides, insecticides, biocides, and wood preservatives, To investigate the effects of pentachlorophenol (PCP) on anaerobic digestion system, an experimental study was carried out in which simulated PCP-contaminated sewage water was treated using a batch reactor. The study revealed that the influences of PCP on acidogenic and methanogenic microorganisms. Affected by PCP, the fermentation type of system was transformed from butyric acid type to propionic acid type.Moreover, biogas production rate and methane content were less. PCP inhibited the activity of methane bacteria significantly: during the series of PCP addition (PCP concentration was 0, 14.9, 19.1, and 29.5 mg/L, respectively), the higher the PCP concentration was, the more serious the inhibition effect was. The removal rate...

The shifted Chebyshev polynomials and Floquet theory are both adopted for the prediction regenerative chatter stability and Hopf bifurcation in milling. The influences of the system parameter on the stability of the milling system have been analyzed. The stability lobe diagrams are obtained. The result shows that the shifted Chebyshev polynomials method is more accurate than the semi-discretion scheme for spindle speed lower than 3500 round per minutes. The stability in milling can well be predicted by the cutting depth and feed rate lobes diagrams. Only Hopf bifurcations are detected by the Eigen-value analysis. The stable solution transform from the stable equilibrium point to the quasi-periodic oscillation after Hopf bifurcation.

Surface tension of sodium aluminate solution and the contact angle between Al(OH)3 particles and aluminate solution were measured, then the dependence of Al(OH)3 solubility on its particle size was calculated and thus the variation of the critical nucleus sizes was determined based on the Ostwald ripening formula. The results show that the Al(OH)3 solubility in sodium aluminate solution decreases with the increment of particle size, and the critical nucleus sizes increase with the rise of alkali concentration, caustic ratio and precipitation temperature. The results also imply that the presence of small particles in seeded precipitation system is an important factor to limit the depth of precipitation.

The oil recovery of CO2huff and puff well in ultra-low permeability reservoir is low. It is necessary to take measures to increase the development benefit. So the relevant development examples and theoretical research are taken into account in this paper, and according to liquid property and reservoir characteristics, the screening and evaluating system and grading evaluation standard of CO2 huff and puff well location is established. Based on fuzzy comprehensive evaluation, screening steps of CO2 huff and puff well location in ultra-low permeability reservoir is also established. The effect of the method has been proved by field practice. The result provides theoretical and technological support. And it provides reference for similar reservoirs.

Due to the gathering of hazard materials, petrochemical plant always has extrusive fire and explosion risk. Unreasonable plant layout could bring high accident frequency, secondary accident possibility, and immense financial loss. The expected characters of a safe layout were analysed at first in this work, and then four key metrics were proposed to evaluate the safety performance of the layout. These four metrics are accident triggered likelihood degree, improper degree of domino risk , improper degree of facility damage risk/human injury risk and evacuation difficulty degree . Based on the character analysis, the mathematical representations of the four metrics were also preliminarily analyzed.

After oil spills in the coastal aquatic environment, the physical and chemical properties of the spilled oil may change under the influence of the chemical dispersant and form emulsions in the water. This paper presents the results of a laboratory study on the influence of chemical dispersant to the properties of crude oil. The experiments were conducted using two widely-used surfactant GM-2 and BH-X, two crude oil samples and artificial seawater. Density, viscosity and emulsification rate of crude oil with different amounts of dispersant added was measured. The results show that viscosity of the crude oil was highly influenced by the chemical dispersant. The maximum emulsification rate of the Saudi Arabian middle crude oil was 54.1% and 57.4% with the dispersant to oil ratio above 0.8, whereas the emulsification rate of the heavy oil was significantly lower than the middle oil with both of the two types of chemical dispersant.

5 highly efficient hydrocarbon-degrading mixed bacteria were obtained from the petroleum-contaminated soil samples by the traditional method of enrichment and acclimation. The KL9-1 consortium had a wide temperature tolerance range and higher hydrocarbon degrading ability. The degradation rate of thin oil and heavy oil was up to 43.27% and 20.09% respectively through 7 d at 45oC. After several times of isolation and purification, three dominant strains with the capability of hydrocarbon-degrading were obtained, and their petroleum degradation rates were all over 30%. According to its morphological and 16S rDNA sequence characteristics, KL9-1-1 and KL9-1-2 were identified as Pseudomonas sp., and the KL9-1-3 was identified as Rhodococcus sp..

When oil spills in the coastal environment, the spilled oil may interact with the suspended particulate matter in the water column to form oil-SPM aggregates (OSAs). This process has been recognized to enhance natural cleansing of oiled shorelines. This laboratory study was conducted using SPM samples with different particle size distribution and mineral composition, two crude oil samples, filtered natural seawater, and a reciprocating shaker. The sediment-to-oil ratio was kept constant to 1 in all the experiments. The oil trapped in negatively buoyant OSAs was measured using an Infrared Oil Content Analyzer. Results showed that OSA formation increased with the decrease of the sediment size, the maximum oil trapped in settled OSAs was 182 mg oil/ g sediment when OSAs were formed with kaolinite and CST180 crude oil.

The treatment of high salinity wastewater treatment in refinery has been widely noticed due to more and more stringent laws and regulations. In the paper, in order to deal with the high salinity wastewater efficiently, a MED process was performed, and mathematical modeling was established to discuss the effect of feed steam on MED dealing with high-salinity wastewater. The results indicated that the temperature of steam produced by different low-temperature heat and pressures of the steam could all affect the MED system obviously. For example, the mass of pure water increased slightly with the increase of feed steam temperature in 3 effects system. With the same pressure feed steam, more mass of pure water was produced by fewer effects system, etc. This paper would provide a very useful reference for the high-salinity wastewater reduction via MED process in petroleum refinery.

A bioflocculant M-1 produced by Enterobacter sp. EP3 was investigated with regard to its flocculanting characteristics and mechanism. 2.0 mg/l M-1 showed the maximum flocculating activity of 96% in 5.0g/l Kaolin suspension containing 8mM CaCl2 and that its flocculating activity was more than 80% in a wide pH range (4.0-12.0). Chemical analyses indicated that the biopolymer M-1 was mainly a polysaccharide, mainly consist of rhamnose and glucose with a molar ratio of 9:1. Infrared spectrophotometry showed the presence of carboxyl, hydroxyl and methoxyl groups in M-1 molecular. Flocculation of Kaolin suspension with M-1 acted as a model to explore the flocculating mechanism in which bridging mediated by Ca2+ was proposed as the primary action based on the experimental observations.

A response surface methodology was applied to optimize the bioremediation condition of hydrocarbon in soil by microbial consortium KL9-1. A four-level Box-Behnken factorial design was employed to study the relationship of independent variables and dependent variable by applying pH value, inoculation amount of microbial consortium KL9-1, ratio of nitrogen and phosphorus (N/P ) and surfactant (SDBS) concentration as independent variables (factors) and crude oil removal rate as dependent variable (response). Then the statistically significant model was obtained and numerical optimization based on desirability function was carried out for pH 7.0, inoculation amount 50.0 mL, N/P 2: 1 and SDBS concentration 4.0 g, and the hydrocarbon removal rate reached as high as 52.58%. The predictive values showed good agreement with the experimental values under the optimization conditions, by standard variance

Microorganisms with high oil-degrading performance are essential for bioremediation of soil contaminated with crude oil. A positive end dilution method was employed for the selection of crude oil-degrading functional consortium from contaminated soil. The selected consortium was consisted of Rhizobiales sp., Pseudomonas sp., Brucella sp., Bacillus sp., Rhodococcus sp., Microbacterium sp. and Roseomonas sp. and removed nearly 52.1% of crude oil at initial concentration of 10,000 mg l−1 at 30 °C within 7 days, with removal of aliphatic hydrocarbons by 71.4% and aromatic hydrocarbons by 36.0%, respectively. The effectiveness of the consortium for bioaugmentation was confirmed with microcosm test by contaminated soil (1.0 kg) from Karemary Oilfield, China. The removal efficiency of crude oil was enhanced to >50% in microcosms with the consortium compared with 8–13% or lower in controls over a 60 day period. The crude oil removal reaction was probably first order reaction and the rate was greatly enhanced by bioaugmentation. Supplementation of nitrogen and phosphate sources had limited effect on the oil removal in the tested soil.

This document discussed a biofilter packing with complex filler, which was inoculated by a kind of toluene-degrading microorganism. The toluene-degrading microorganism(JBJ-3), which was isolated from activated sludge from a wastewater treatment plant of refinery, was classified as Pseudomonas sp. initially by physiological and biochemical tests. The removal efficiency of JBJ-3 reached to 93.73% for 48h. Complex filler consisted of wood chip, peat and compost etc. It has high amounts of organic matter, high specific surface area, good water holding capacity, good permeability, varied microbial system, and contains intrinsic nutrients. The complex filler could inoculate Pseudomonas sp. JBJ-3 well. And under the different inlet concentrations of toluene, the overall removal efficiency had reached above 92%. And the biofilter packing complex filler showed a good resistance to shock load.

This paper presented a new CSMA protocol, which is named probability detection and non-persistent joint control for multi-channel random multi-access (PDNMRM). Throughput of system, throughput of different priority and packet delay are presented by theoretical calculations. The protocol controls the number of sleep node by choosing the value of p, and control system to sleep in idle period. By giving an analysis of energy efficiency of PDNMRM, we got the result that PDNMRM has longer life cycle. Then, the paper proved that theoretical analysis is correct by simulation experiment.

In this paper we consider the polling system with multiple vacations an bulk arrival using M-gated services in continuous time. By the imbedded Markov chain theory, the generating functions of queue length at the station is obtained. Then computational equations are explicitly determined for the mean queue length. Especially we can obtain some corresponding results under some especial cases. The results reveal that our system model can guarantee better QoS and system stability, and it has better efficiency than that of traditional gated service.

The contention-collision elimination access mode is a new kind of access mode in star LAN. It can be divided into six different models according to the working principle. The mathematical analysis and performance evaluations for the Ist, IInd, IIIrd and Vth models have been presented in our previous papers. The performance evaluation for the IVth model is discussed in this paper by calculating several important parameters in steady-state i.e. the customer's transfer probability Pij, the mean number of customers M, and the mean waiting time W. Performance comparisons between the IVth model and the IInd model are also presented.

Embryonic stem (ES) cells rely on growth factors provided by feeder cells or exogenously to maintain their pluripotency. In order to identify such factors, we have established sub-lines of STO feeder cells which exhibit variable ability in supporting ES cell self-renewal. Functional screening identifies WNT5A and WNT6 as STO cell-produced factors that potently inhibit ES cell differentiation in a serum-dependent manner. Furthermore, direct activation of beta-catenin without disturbing the upstream components of the WNT/beta-catenin pathway fully recapitulates the effect of WNTs on ES cells. Importantly, the WNT/beta-catenin pathway up-regulates the mRNA for Stat3, a known regulator of ES cell self-renewal in the mouse. Finally, LIF is able to mimic the serum effect to act synergistically with WNT proteins to inhibit ES cell differentiation. Therefore, our study reveals part of the molecular mechanisms by which the WNT/beta-catenin pathway acts to prevent ES cell differentiation through convergence on the LIF/JAK-STAT pathway at the level of STAT3.

The contention–collision elimination access mode is a new kind of access mode in star LAN. It can be divided into six different models according to its working mechanism. The mathematical analyses for the Ist, IIIrd and Vth models have been presented and discussed in previous papers. In this paper, the IInd model is studied, and results are compared with the Ist one. The results in this paper have important values in design the integrated services local area network.

In this article, we adopt the Markov Chain theory and Probability generating functions as analysis and study of the function methods. With complete service rules and limited rules constructed passing ability and control analysis model of logistics nodes of distribution center. From the mean waiting time of through passing logistics nodes to analyze out its control of the priority and presents the corresponding simulation experiment results, research and analysis of the conclusion.

This paper presents a dynamic time-slot control random multi-access (DTCRM) protocol with two-dimensional probability for ad hoc network. For this protocol, the system time is slotted dynamically realized by the location of packets arriving time and the choice of two parameters p1 and p2. A mathematical model is given for the DTCRM protocol using the average cycle method. Simulation results verify the high accuracy of the analysis. The results show that the DTCRM protocol is better than the typical protocols.

In order to improve the quality of service (Qos) and channel utility of wireless communication networks, to present the double clocks random multi-access protocol with multi-channel and two-dimensional probability (DCRM) protocol. By means of double clocks control mechanism realized by combination of continuous and slotted clocks to promise higher channel utility. The average period method was used to get throughputs of system and each priority. Analysis shows that the DCRM protocol can ensure higher throughput and Qos demands which support multi-services and higher priority service. What is more, provide a feasible method to realize the system with the DCRM protocol in theory.

It is analyzed and studied non-isolated double time slots algorithm of conflict resolution. The average resolution times analytic expression, resolution efficiency analytic expression and the average resolution delay analytic expression of conflict packet are exlicitly obtained. Furthermore, some exiting problems of doubel time slots algorithm are discussed and some measures of improve performance of algorithm are given.

To investigate the clinical effects of PHILOS plate with injectable artificial bone for the treatment of proximal humeral fractures in elderly patients.From March 2007 to March 2009,17 patients who suffered from proximal humeral fractures were retrospectively studied. There were 7 males, 10 females, with an average age of 71 years (ranged, 66 to 81 years). Nine patients were caused by falling, seven patients were caused by traffic accidents,and one patient was hit by heavy object. According to the Neer classification, 9 patients were type III and 8 patients were type IV. All the patients were treated with PHILOS plate internal fixation combined with injectable artificial bone. Assessment was based on the Constan-Murley shoulder score and percentage Constant-Murley score.The mean period of follow-up was 16 months (ranged, 8 to 25 months). All the patients obtained bone union in an average of 3 months (2.5 to 3.5 months). There were no complications such as deep infection, nonunion or failure of fixation. The Constant-Murley score of the injured side was mean (86.50 +/- 10.50) (ranged, 75 to 95). The clinical outcomes were excellent in 9 cases, good in 6 cases, moderate in 2 cases.The treatment of proximal humeral fractures in elderly patients with application of PHILOS plate combined with injectable artificial bone can get satisfactory clinical effect especially suitable for osteoporosis and comminuted proximal humeral fractures.

Based on the ideas of priority-based service and dynamic load adaptation, this article proposes a polling scheduling strategy fit for the MAC access protocol of WLAN, making possible the service of the two-class priority station polling system under the mixed policy of exhaustive and gated services, optimizing the services of the system in time of load change input via adjustment of the times of the access gated services, and strengthening the instantaneity and fairness of multimedia transmissions in wireless system. The theoretical model of this protocol is established through Markov chain and probability generating function. Mathematical analysis is made on the mean queue length and the mean inquiry cyclic time of the common queue and the key station. It turns out that the findings from theoretical analysis correspond well with those from simulated experiments.