A Pd and norbornene-catalyzed ortho-arene amination via Catellani-type C-H functionalization is reported. Aryl halides are used as substrates; N-benzoyloxyamines and isopropanol are employed as the ...amine source (oxidant) and reductant respectively. Examples are provided in 50-99% yields with high functional group tolerance. This method gives complementary site selectivity at the ortho- instead of ipso-position of aryl halides.
Pressurized water reactor (PWR) is the most widely used nuclear fission reactor, and the renaissance of fission energy industry needs the safe, stable and efficient operation of PWRs. Power-level ...control technique which strengthens the closed-loop stability and dynamic performance is meaningful to build a strong operation strategy for PWRs. In this paper, after extending the shifted-ectropy of thermodynamic systems to that of transport systems, a proportional-differential (PD) power-level controller is proposed for PWRs based on the physically-based approach. A sufficient condition for this PD controller to provide the globally asymptotic stability of those reactor state variables is established. Numerical simulation results not only verify the correctness of the theoretic results but also illustrate the relationship between the control performance and controller parameters. The meaning of this result is giving a theoretic explanation to why the simple PD control is effective for PWR power-level regulation practically.
The modular high temperature gas-cooled reactor (MHTGR) is an important type of small modular reactors (SMRs) with inherent safety. It is clear that power-level control is crucial in providing safe ...and stable operation as well as in realizing load-following function so that the MHTGRs can be grid-appropriate. However, there always exists the reactor parameter uncertainty and control input nonlinearity such as saturation and dead-zone practically, which seriously intensify the difficulty in designing power-level control. Thus, it is quite necessary to study MHTGR power-level control method against reactor parameter variation as well as control input saturation and dead-zone. Motivated by this, model-free MHTGR power-level control laws against the input saturation, dead-zone and both saturation and dead-zone are proposed in this paper, which are not only insensitive to reactor parameter but also able to compensate the control input nonlinearities. It is proved theoretically that these newly-built MHTGR power-level control laws guarantee strong closed-loop stability. Numerical simulation results illustrate the relationship between the control performance and some parameters of the controllers and input nonlinearities.
Reported herein is a palladium/norbornene‐catalyzed ortho‐arene acylation of aryl iodides by a Catellani‐type CH functionalization. This transformation is enabled by isopropyl carbonate anhydrides, ...which serve as both an acyl cation equivalent and a hydride source.
Double (re)agent: A palladium/norbornene‐catalyzed ortho‐acylation of aryl iodides was developed, and is enabled by isopropyl carbonate anhydrides, which function as both an acyl cation equivalent and a hydride source. This reaction exhibits excellent functional‐group compatibility and broad substrate scope. Heterocycle moieties can be tolerated on both the aryl and acyl partners. FG=functional group.
After the Fukushima nuclear accident, much more attention has to be drawn on the safety issues. The improvement of safety has already become the focus of the developing trend of the nuclear energy ...systems. Due to the inherent safety feature and the potential economic competitiveness, the modular high temperature gas-cooled reactor (MHTGR) has been seen as the central part of the next generation of nuclear plant (NGNP). Power-level control is one of the key techniques that guarantee the safe, stable and efficient operation for nuclear reactors. Since the MHTGR dynamics has the features of strong nonlinearity and uncertainty, in order to improve the operation performance, it is meaningful to develop the nonlinear adaptive power-level control law for the MHTGR. Based on using the natural dynamic features beneficial to system stabilization, a novel nonlinear adaptive power-level control is given for the MHTGR in this paper. It is theoretically proved that this newly-built controller does not only provide globally asymptotic closed-loop stability but is also adaptive to the system uncertainty. This control law is then applied to the power-level regulation of the pebble-bed MHTGR of the HTR-PM power plant. Numerical simulation results show the feasibility of this control law and the relationship between the performance and controller parameters.
To show the synthetic utility of palladium/norbornene (Pd/NBE) cooperative catalysis, here we report concise syntheses of indenone‐based natural products, pauciflorol F and acredinone A, which are ...enabled by direct annulation between aryl iodides and unsaturated carboxylic acid anhydrides. Compared to the previous indenone‐preparation approaches, this method allows simple aryl iodides to be used as substrates with complete control of the regioselectivity. The total synthesis of acredinone A features two different Pd/NBE‐catalyzed ortho acylation reactions for constructing penta‐substituted arene cores, including the development of a new ortho acylation/ipso borylation.
A straightforward method for indenone synthesis was achieved by Pd/NBE‐catalyzed annulation between simple aryl iodides and unsaturated carboxylic acid anhydrides. This method enabled streamlined syntheses of pauciflorol F and acredinone A.
Fault diagnosis is crucial for the operation of energy systems such as nuclear plants, and heavily relies on various types of sensors for temperature, pressure, concentration, etc. Due to the ...redundancy of sensors in each energy system, the sensor selection scheme can deeply influence the diagnostic efficiency. In this paper, a Boolean network (BN) with its linear representation is proposed for describing the fault propagation among sensors. Both the sufficient condition of fault detectability and that of fault discriminability are given. Then, a sensor selection method for fault detection and discrimination is proposed. Finally, the theoretic result is applied to realize the diagnosis oriented sensor selection for a nuclear steam supply system based on a modular high temperature gas-cooled reactor (MHTGR). The computation and simulation results verify the correctness of the theoretical results.
Because of its strong inherent safety, the modular high temperature gas-cooled nuclear reactor (MHTGR) has been regarded as the central part of the next generation nuclear plants (NGNPs). Power-level ...control is one of the key techniques which provide safe, stable and efficient operation for the MHTGRs. The physically-based regulation theory is definitely a promising trend of modern control theory and provides a control design method that can suppress the unstable part of the system dynamics and remain the stable part. Usually, the control law designed by the physically-based control theory has a simple form and high performance. Stimulated by this, a novel nonlinear dynamic output feedback power-level control is established in this paper for the MHTGR based upon its own dynamic features. This newly-built control strategy guarantees the globally asymptotic stability and provides a satisfactory transient performance through properly adjusting the feedback gains. Simulation results not only verify the correctness of the theoretical results but also illustrate the high control performance.
Aims/Introduction
The aim of the present study was to identify candidate differentially expressed genes (DEGs) and pathways using bioinformatics analysis, and to improve our understanding of the ...cause and potential molecular events of diabetic nephropathy.
Materials and Methods
Two cohort profile datasets (GSE30528 and GSE33744) were integrated and used for deep analysis. We sorted DEGs and analyzed differential pathway enrichment. DEG‐associated ingenuity pathway analysis was carried out. The screened gene expression feature was verified in the db/db mouse kidney cortex. Then, rat mesangial cells cultured with high‐concentration glucose were used for verification. The target genes of transcriptional factor E26 transformation‐specific‐1 (ETS1) were predicted with online tools and validated using chromatin immunoprecipitation assay quantitative polymerase chain reaction.
Results
The two GSE datasets identified 89 shared DEGs; 51 were upregulated; and 38 were downregulated. Most of the DEGs were significantly enriched in cell adhesion, the plasma membrane, the extracellular matrix and the extracellular region. Quantitative reverse transcription polymerase chain reaction analysis validated the upregulated expression of Itgb2, Cd44, Sell, Fn1, Tgfbi and Il7r, and the downregulated expression of Igfbp2 and Cd55 in the db/db mouse kidney cortex. Chromatin immunoprecipitation assay quantitative polymerase chain reaction showed that Itgb2 was the target gene of transcription factor Ets1. ETS1 knockdown in rat mesangial cells decreased integrin subunit beta 2 expression.
Conclusion
We found that EST1 functioned as an important transcription factor in diabetic nephropathy development through the promotion of integrin subunit beta 2 expression. EST1 might be a drug target for diabetic nephropathy treatment.
We have identified candidate differentially expressed genes and pathways by bioinformatics analysis in diabetic nephropathy, which improves our understanding of the cause and potential molecular events of diabetic nephropathy. We found that E26 transformation‐specific‐1 functioned as an important transcription factor in diabetic nephropathy development through the promotion of integrin subunit beta 2 expression.
Power-level regulation is a significant technique for guaranteeing both operation stability and efficiency of nuclear reactors. With the wide application of the digital instrument and control ...platforms, the implementation of modern state-feedback power control strategies, which have the ability of strengthening both the operation stability and efficiency for nuclear reactors, becomes much easier than before. Due to the advanced property of state-feedback power-level control and nonlinearity of reactor dynamics, it is so meaningful to develop nonlinear state-feedback power-level control laws. In this paper, a novel nonlinear state-feedback dissipation power-level control strategy is presented, which guarantees both the asymptotic closed-loop stability and convergent state-observation. Numerical simulation results show the feasibility and relationship between the observer-gain and control performance, and theoretic analysis corresponding to the simulation results is also given.
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