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Electrophilic fluorophosphonium triflates bearing pyridyl (3[OTf]) or imidazolyl (4[OTf])-substituents act as intramolecular frustrated Lewis pairs (FLPs) and reversibly form 1 : 1 adducts with CO2 (5+ and 6+ ). An unusual and labile spirocyclic tetrahedral intermediate (72+ ) is observed in CO2 -pressurized (0.5-2.0 bar) solutions of cation 4+ at low temperatures, as demonstrated by variable-temperature NMR studies, which were confirmed crystallographically. In addition, cations 3+ and 4+ actively bind carbonyls, nitriles and acetylenes by 1,3-dipolar cycloaddition, as shown by selected examples.

This study focuses on improving the Weber model to obtain a more optimised solution, by which we can measure effectively the quality of the voting rules. By introducing the voter’s supporting domai...

The in situ electrophilic fluorination of phosphanes with commercially available bench-stable N-fluorobenzenesulfonimide (NFSI), followed by subsequent methylation of the [N(PhSO2)2]− anion with MeOTf yields a family of electrophilic fluorophosphonium cations as triflate salts. Most of these fluorophosphonium triflate salts are remarkably Lewis acidic and form isolable adducts in stoichiometric reactions with suitable donors such as N,N-dimethylformamide (DMF). Furthermore, their catalytic capabilities were tested in the transformation of formamides into N-sulfonyl formamidines in the reaction with Na[N(SO2Ph)2] and the proposed mechanism is validated by DFT calculations.

The purpose of this paper is to study the impact of bounded consumer rationality on the order quantity and profitability of the seller in the advance period and the spot period in the context of the combination of new retail and pre-sale. In this paper, we develop a seller order model in the context of the combination of new retail and pre-sale, with and without reference price dependence. Besides, the model considers the order cancellation and delayed purchase behavior of consumers. We then discuss the optimal profit and optimal order quantity under different conditions and the effect of different reference price dependence and value-added offline service on them. Our research shows that: First, the seller tends to set the deposit too low in pre-sales. Second, reference price dependence has different effects on order quantities in different periods. The seller should pay more attention to the impact of reference price dependence. Third, on the whole, consumer rationality benefits the seller. The seller, or the public policymaker, can benefit new retail businesses by increasing consumer rationality. Last, in the new retail context, an increase in offline service value-added, even if it increases total order quantity, is not always beneficial to the seller and may reduce profits. Therefore, the seller should weigh all factors to determine the optimal value-added offline services.

Electrophilic fluorophosphonium triflates bearing pyridyl (3[OTf]) or imidazolyl (4[OTf])‐substituents act as intramolecular frustrated Lewis pairs (FLPs) and reversibly form 1 : 1 adducts with CO2 (5 + and 6 +). An unusual and labile spirocyclic tetrahedral intermediate (7 2+) is observed in CO2‐pressurized (0.5–2.0 bar) solutions of cation 4 + at low temperatures, as demonstrated by variable‐temperature NMR studies, which were confirmed crystallographically. In addition, cations 3 + and 4 + actively bind carbonyls, nitriles and acetylenes by 1,3‐dipolar cycloaddition, as shown by selected examples., Extending the FLP library: Electrophilic fluorophosphonium triflates bearing pyridyl or imidazolyl substituents act as intramolecular N/P frustrated Lewis pairs that are capable of small molecule activation, that is, reversible CO2 sequestration and binding of carbonyls, nitriles and acetylenes.

Accepting that suppliers' capability for green transformation of manufacturing systems is private information and that the efforts made in the process of transformation invisibly involve private actions of buyers, we construct an outsourcing model including transformation services before project delivery and maintenance services within the warranty period after project delivery and research the optimal outsourcing contract design for buyers. We find that the buyer can design a set of contract menus, including fixed compensation and variable compensation related to the quantity of energy conservation and emission reduction (ECER), to identify suppliers with different transformation capabilities and encourage them to make the best efforts under asymmetric information. Second, to identify the suppliers' transformation capability, the buyer needs to pay information rent to the supplier with high transformation ability. Meanwhile, the existence of asymmetric information will make the supplier with low transformation ability exert insufficient effort, and the existence of asymmetric information will always reduce the buyer's expected utility. In addition, the example analysis shows that asymmetric information always reduces the expected number of ECERs of the buyer. Therefore, it is suggested that the government should consider screening the transformation ability of green technology suppliers, disclose to the market and recommend suppliers with high transformation ability to reduce the negative impact caused by asymmetric information.

We present an ab initio investigation of below-threshold harmonic generation (BTHG) of Cs atom in intense mid-infrared laser fields by accurately solving the time-dependent Schrödinger equation. We find that the spectra yield in BTHG of Cs atom dependents on the light intensity in the multiphoton ionization regime, and the bound states play an important role in the channel selection process for BTHG. Combining with wavelet time-frequency transform, semiclassical trajectories simulation, and quantum channel analysis, the dynamical origin of the BTHG is uncovered.

Silver tungstate was successfully developed as a bifunctional catalyst for the ligand-free carboxylation of various terminal alkynes with electron-withdrawing or electron-donating groups under atmospheric pressure of carbon dioxide (CO2) at room temperature. In this protocol, dual activation – i.e., the terminal alkyne activated by silver, and CO2 activation by the tungstate anion – was verified using nuclear magnetic resonance spectroscopy, and means that this reaction can be run under ambient conditions. Notably, this protocol can be applied to the preparation of a phenylacrylate derivative by a cascade reaction using phenylacetylene, CO2 and benzylamine as starting materials.

An efficient method for the synthesis of 3a-hydroxyisoxazolo[3,2-a]isoindol-8(3aH)-ones from CO2, terminal alkynes, EtBr, and NHPI (N-hydroxyphthalimide) was developed through a tandem carboxylation/annulation strategy catalyzed by a copper(I)/phosphine system. This one-pot multicomponent reaction was conducted at atmospheric CO2 pressure to afford the target products in good to excellent yields under mild conditions. Notably, a wide range of functional groups were tolerated in this procedure. This protocol with simultaneous formation of four novel bonds i.e. two C–C bonds and two C–O bonds represents an efficient methodology for upgrading CO2 into heterocycles.

Chemical fixation of CO2 to value-added products/materials/fuel has attracted more and more attention from both academia and governmental agencies all over the worldsince CO2 is an easily available and sustainable C1 resource with the advantage of being abundant, nontoxic, nonflammable and renewable. Synthesis of organic carbonates starting from CO2 is one of the most promising methodologies and has been widely investigated. The use of CO2 and 1,2-diols can bring many advantages, such as reusing the byproducts generated in the industrial dimethyl carbonate (DMC) process and simplifying the post purification process. In this paper, synthetic methods with reaction mechanism of ethylene carbonate (EC), propylene carbonate (PC) and glycerol carbonate from CO2 and ethylene glycol (EG), or propylene glycol (PG) or glycerol are systematically discussed.

A random lattice order decision analysis method is proposed based on an interval probability distribution preference vector by way of entropy theory, focusing on a decision preference system in which preference relation probability is described by interval values and the decision maker’s behavior is also considered. The preference characterization of decision makers is extended from four varieties of relations to seven varieties of preference relations. In addition to the concept, property, and operation rules of interval probability, the concept of interval-valued distribution preference vectors and the relative entropy on the lattice-ordered preference system are given. Then, the interval probability can be more precisely determined, and the weighting interval probability is transformed into the interval probability weight. The ER nonlinear optimization model based on preference entropy is established, individual preferences are aggregated by applying the priority rule and the intersection rule, and the specific steps of decision making are given. Finally, the feasibility and effectiveness of the approach proposed in this paper are illustrated with a numerical example.

Selective oxidation of sulfides was successfully performed by employing phenyliodine diacetate as an oxidant with the catalysis of TsOH in aqueous solution under mild conditions. Sulfoxides were formed with 1.1 equiv of PhI(OAc)2 at room temperature; whereas sulfones were obtained in the presence of 2.1 equiv of PhI(OAc)2 at 80 °C under otherwise identical conditions. Notably, various sulfides were converted to corresponding sulfoxides or sulfones in good to high yields by this metal-free protocol.

In this study, a relevant evaluation index system was established based on the level of information, the sense of social responsibility, as well as factors such as management capacity. The partial order preference has also been determined under the premises that the evaluation index are stochastic, intuitionistic fuzzy and ordinal and the pre-order preference structure is extended to partial order preferences. The combined multi-attribute decision- making model is developed with the uncertain weight of evaluation index, followed by the decision-making process and decision-making method. The feasibility and effectiveness of the approach proposed in this study are illustrated by case study.

Carbon dioxide utilization has continued to capture the interest of chemists worldwide due to global warming associated with positive carbon accumulation. As an environmentally friendly C1 feedstock, the reaction of carbon dioxide has been extensively investigated for several decades. On the other hand, acrylic acid is a valuable industrial product that is widely used for various important purposes in industry. From the point view of atom- and process-economical chemistry, the most concise and promising route for acrylic acid derivatives synthesis would be direct carboxylation of olefins or alkynes with carbon dioxide. In this review, we would like to discuss and update the latest advances on synthesis of acrylic acid derivatives from unsaturated hydrocarbons and carbon dioxide.

Although the financial crisis is seemly over, but its impact on the global economy is still spreading, and also make people pay more attention to the improvement and operation of the economic and financial system, the development of the logistics industry in this financial crisis has also been confronted with great challenge, in this case, the concept of logistics finance is more widely known by people. While logistics finance provides a good opportunity to the development of logistics industry, it also involves enormous risk. As the financial supervision system is incomplete, enterprise credit evaluation and supervision system is not perfected, risks of the logistics enterprises participate in the logistics finance are more obvious, and researches of this aspect will appear more valuable. Therefore, this paper established a game theory tripartite game model of logistics financial participants, on the base, risks of logistics enterprises participate in the logistics financial business were analyzed, and show the corresponding conclusions and recommendations.

In this paper, ferric alginate fibers was prepared by wet spinning of sodium alginate into a coagulating bath containing ferric chloride. The carbon-supported nanoscale zero-valent iron fibers (CSNZVIF) were obtained through thermal degradation of ferric alginate fiber at 900°Cunder N2atmosphere. The product was characterized by field emission scanning electron microscopy (FESEM), X-ray power diffractometer (XRD), and Brunauer-Emmett-Teller (BET) surface area. It was found that zerovalent iron particles were well dispersed in the amorphous carbon fibers. CSNZVIF has high surface areas of 352 m2/g. The existence of carboxylic group and hydroxyl group in ferric alginate structure unit plays key role in the formation of carbon-supported nanoscale zero-valent iron fibers. Fe3+was reduced to Fe0by hydroxyl group and as-formed amorphous carbon during heating under N2. This thermal degradation and self-reduction reaction of ferric alginate fiber is potentially scalable to large production and continuous processing for preparing CSNZVIF.

A number of dry bridges have been built to substitute for the roadbed on the Qinghai-Tibet Railway, China. The aim of this study was to investigate the exothermic process of cast-in-place (CIP) pile foundation of a dry bridge and its harm to the stability of nearby frozen ground. We present 3D heat conduction functions of a concrete pile and of frozen ground with related boundaries. Our analysis is based on the theory of heat conduction and the exponent law describing the adiabatic temperature rise caused by hydration heat. Results under continuous and initial conditions were combined to establish a finite element model of a CIP pile-frozen ground system for a dry bridge under actual field conditions in cold regions. Numerical results indicated that the process could effectively simulate the exothermic process of CIP pile foundation. Thermal disturbance to frozen ground under a long dry bridge caused by the casting temperature and hydration heat of CIP piles was substantial and long-lasting. The simulated thermal analysis results agreed with field measurements and some significant rules relating to the problem were deduced and conclusions reached.

An efficient method for the synthesis of 3a-hydroxyisoxazolo[3,2-a]isoindol-8(3aH)-ones from CO2, terminal alkynes, EtBr, and NHPI (N-hydroxyphthalimide) was developed through a tandem carboxylation/annulation strategy catalyzed by a copper(I)/phosphine system. This one-pot multicomponent reaction was conducted at atmospheric CO2 pressure to afford the target products in good to excellent yields under mild conditions. Notably, a wide range of functional groups were tolerated in this procedure. This protocol with simultaneous formation of four novel bonds i.e. two C–C bonds and two C–O bonds represents an efficient methodology for upgrading CO2 into heterocycles.

Chemical fixation of CO2 to value-added products/materials/fuel has attracted more and more attention from both academia and governmental agencies all over the worldsince CO2 is an easily available and sustainable C1 resource with the advantage of being abundant, nontoxic, nonflammable and renewable. Synthesis of organic carbonates starting from CO2 is one of the most promising methodologies and has been widely investigated. The use of CO2 and 1,2-diols can bring many advantages, such as reusing the byproducts generated in the industrial dimethyl carbonate (DMC) process and simplifying the post purification process. In this paper, synthetic methods with reaction mechanism of ethylene carbonate (EC), propylene carbonate (PC) and glycerol carbonate from CO2 and ethylene glycol (EG), or propylene glycol (PG) or glycerol are systematically discussed.

Selective oxidation of sulfides was successfully performed by employing phenyliodine diacetate as an oxidant with the catalysis of TsOH in aqueous solution under mild conditions. Sulfoxides were formed with 1.1 equiv of PhI(OAc)2 at room temperature; whereas sulfones were obtained in the presence of 2.1 equiv of PhI(OAc)2 at 80 °C under otherwise identical conditions. Notably, various sulfides were converted to corresponding sulfoxides or sulfones in good to high yields by this metal-free protocol.

An efficient CuI-catalyzed carboxylation of terminal alkynes under mild conditions and without the need of any additional ligand is developed.

This paper considers a rumor transmission model with incubation that incorporates constant recruitment and has infectious force in the latent period and infected period. By carrying out a global analysis of the model and studying the stability of the rumor-free equilibrium and the rumor-endemic equilibrium, we use the geometric approach for ordinary differential equations which is based on the use of higher-order generalization of Bendixson’s criterion. It shows that either the number of rumor infective individuals tends to zero as time evolves or the rumor persists. We prove that the transcritical bifurcation occurs atR0crosses the bifurcation thresholdR0=1by projecting the flow onto the extended center manifold. Since the rumor endemic level at the equilibrium is a continuous function ofR0, as a consequence for successful eradication of the rumor, one should simply reduceR0continuously below the threshold value 1. Finally, the obtained results are numerically validated and then discussed from both the mathematical and the sociological perspectives.

A method of group decision-making based on the preference distance is proposed,when the preference information is provided by decision maker with ordinal formal preference structure,and the decision makers' power with incomplete certain information. The distance of preference relation is defined ,and some available property and conclusion are given. The group aggregation procedure is given when decision makers' power with certain information. Using the distance of preference relation , the Mathematics models are established to aggregate individual preference when decision makers' power with incomplete certain information. The feasibility and effectiveness of the approach proposed in this paper are illustrated with a numerical example.

Service quality is the first consideration of the passenger airlines, which will have direct effect on their reputation, economic benefit, even their survival. Airlines can understand their relative competitive advantages by the scientific and subjective evaluation method. A method of multi-criteria analysis based on similarity degree between fuzzy linguistic is proposed, when the service quality perceived by customer is expressed using fuzzy linguistic .The customers' perception assessment is aggregated, the similarity degree between airlines and positive ideal airline and negative ideal airline by utilizing similarity relations, the comprehensive preference of customers about service quality is gained, the preference structure possessing partial order characteristic. Example shows that the method is scientific and effective

The CuI-catalyzed carboxylation of terminal alkynes with CO2 and alkyl halides using ethylene carbonate as the solvent under mild conditions was studied. DFT calculations reveal that the energy barrier for CO2 insertion into the sp-hybridized Cu-C bond could be reduced by employing ethylene carbonate as the solvent. Notably, the procedure was conducted under ambient CO2 pressure without any external ligands. A broad range of substrates with electron-withdrawing groups or electron-donating groups gave the corresponding products in reasonable yields.