科技人才对河南省制造业技术创新的影响研究--基于人才开发环境视角

文章选取2010—2021年河南省26个制造业行业的面板数据,从人才开发环境视角,考察科技人才对河南省制造业技术创新的影响。研究发现,科技人才能够有效促进河南省制造业技术创新,经过稳健性检验和内生性处理后结论依然成立。行业异质性检验表明,科技人才能够有效促进河南省低技术行业创新,而对高技术行业的影响不显著。门槛效应检验表明,政策环境存在单门槛效应,在其大于门槛值时,科技人才对河南省制造业技术创新的促进作用更强;创新环境存在双门槛效应,在其大于第二门槛值时,科技人才对河南省制造业技术创新才表现为促进作用;制度环境存在单门槛效应,在其小于门槛值时,科技人才对河南省制造业技术创新的促进作用更强。

Effect of strawberry vein banding virus and strawberry mottle virus co-infection on the growth and development of strawberry

Strawberry mottle virus(SMoV)and strawberry vein banding virus(SVBV)cause diseases on strawberry plants,but the effect of coinfection of SMoV and SVBV on the growth,development,and defense system of strawberry(Fragaria×ananassa Duchesne)remains unknown.We investigated the effect of SMoV and SVBV coinfection on strawberry cultivar‘Benihope’.The results showed that stem diameter,leaf size,leaf number,relative chlorophyll content,total chlorophyll content,photosynthetic parameters,and stomatal aperture of SMoV and SVBV co-infected strawberry(VIS)plants were in a weaker level than uninfected control plants,indicating that viruses inhibited the growth and photosynthesis of strawberry plants.Furthermore,the initiation of flowering and fruiting stages of VIS plants were delayed by about three weeks compared with the controls,and the fruiting period was shortened,demonstrating that the reproduction of VIS plants was inhibited.Fruit quality was damaged in VIS plants due to a significant increase in fruit firmness and titratable acidity and decrease in total soluble solid content than control fruits.More dead cells and H_(2)O_(2) accumulated along the veins of VIS leaves,and the content of abscisic acid and catalase activity significantly increased,whereas anthocyanin content was lower than that of control plants.The results demonstrate that SVBV and SMoV coinfection inhibits the growth and development of‘Benihope’strawberry plants,and the plants respond to viruses by regulating stomatal aperture,the accumulation of ABA and antioxidants.To our knowledge,this study contributes information to understand how both viruses impair the strawberry growth and development for the first time.

Incidence,genomic diversity,and evolution of strawberry mottle virus in China

Strawberry mottle virus(SMoV)is one of the most common viruses infecting strawberries,causing losses to fruit yield and quality.In this study,165 strawberry leaf samples were collected from six provinces of China,46 of which tested positive for SMoV.The complete genome sequences of 11 SMoV isolates were obtained from Liaoning(DGHY3,DGHY16-2,DGHY17,DGHY20-2,DGHY21,DGHY26-2),Shandong(SDHY1,SDHY5,SDHY31-2,SDHY33-2),and Beijing(BJMX7).The RNA1 and RNA2 nucleotide identities between the 11 Chinese isolates were 95.4-99.3%and 96.3-99.6%,respectively,and they shared 78.4-96.6%and 84.8-93.5%identities with the available SMoV isolates in GenBank.Recombination analysis revealed that Chinese isolate SDHY33-2 and Canadian isolates Ontario and Simcoe were recombinants,and recombination events frequently occurred in the 3’UTR of SMoV.Phylogenetic analysis showed that in an RNA1 tree,most Chinese isolates clustered into the same group while isolate DGHY17 clustered into another group together with Czech isolate C and three Canadian isolates.In an RNA2 tree,all Chinese isolates clustered into a single group.The phylogenetic analysis based on nucleotide sequences was consistent with the results based on coat protein(CP)and RNA-dependent RNA polymerase(RdRp).Further evolutionary analysis indicated that negative selection drives SMoV evolution,and gene flow plays a major role in genetic differentiation.Additionally,reassortment and recombination also influence the evolution of SMoV.To our knowledge,this is the first report of the complete genome of SMoV isolates from China and a detailed analysis of the SMoV population structure.

Magnetic resonance perfusion imaging evaluation in perfusion abnormalities of the cerebellum after supratentorial unilateral hyperacute cerebral infarction

Magnetic resonance imaging （MRI） data of 10 patients with hyperacute cerebral infarction （≤6 hours） were retrospectively analyzed.Six patients exhibited perfusion defects on negative enhancement integral maps,four patients exhibited perfusion differences in pseudo-color on mean time to enhance maps,and three patients exhibited perfusion differences in pseudo-color on time to minimum maps.Dynamic susceptibility contrast-enhanced perfusion weighted imaging revealed a significant increase in region negative enhancement integral in the affected hemisphere of patients with cerebral infarction.The results suggest that dynamic susceptibility contrast-enhanced perfusion weighted imaging can clearly detect perfusion abnormalities in the cerebellum after unilateral hyperacute cerebral infarction.

Selective Separation and Analysis of Pb(II) Using a New Surface Imprinted Multi-Walled Carbon Nanotubes Combined with AAS

A new surface ion-imprinted Multi-walled carbon nanotubes (MCNTs), which was 6,6'-((1E,1'E)-(pyridine-2,6-diyl- bis(azanylyl))bis(methanylylidene))bis(2-allyl-phenol) and Pb(II) complex as functional monomer and template ion was presented for extracting and enrichment traces of Pb(II) ion. Parameters affecting the recovery of Pb(II) have been investigated in detail. The novel IMCNTs display high affinity, specificity, and selectivity for Pb(II) with a maximum uptake capacity of 115.5 mg·g–1 at pH 4.0. Meanwhile, only 11 mins was enough for extracting 98.5% Pb(II) for the IMCNTs. No significant loss in adsorption capacity is observed when the IMCNTs are reused for eleven times. Separation and preconcentration with IMCNTs particles results in a limit of detection of 0.47 μg·L–1 (3σ) and RSD (n = 8) of 1.16% by using atomic absorption spectrophotometer (AAS)

Recent progress of radionuclides separation by porous materials

The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are considered excellent candidates for the separation of radionuclides under complex conditions due to their high specific surface areas, tunable pore structures and controllable functionalities. In this review, we summarized the design, preparation and functionalization of porous materials and their application for separation of radionuclides in the past five years, discussed the separation performance and analyzed the structure-activity relationship between various radionuclides and porous materials, and systematically clarified their characterization and mechanism of different type porous materials. We also introduced the detection, irradiation and chemical toxicity of different reflective radionuclides.

Application of graphene oxides and graphene oxide-based nanomaterials in radionuclide removal from aqueous solutions

With the fast development of nanoscience and nanotechnology,the nanomaterials have attracted multidisciplinary interests.The high specific surface area and large numbers of oxygen-containing functional groups of graphene oxides(GOs) make them suitable in the preconcentration and solidification of radionuclides from wastewater.In this paper,mainly based on the recent work carried out in our laboratory,the efficient elimination of radionuclides using GOs and GO-based nanomaterials as adsorbents are summarized and the interaction mechanisms are discussed from the results of batch techniques,surface complexation modeling,spectroscopic analysis and theoretical calculations.This review is helpful for the understanding of the interactions of radionuclides with GOs and GO-based nanomaterials,which is also crucial for the application of GOs and GO-based nanomaterials in environmental radionuclide pollution management and also helpful in nuclear waste management.

One-pot synthesis of arginine modified hydroxyapatite carbon microsphere composites for efficient removal of U(Ⅵ) from aqueous solutions

Uranium was not only the main source of nuclear energy but also one of the long-lived radionuclide.Herein, a novel arginine modified hydroxyapatite carbon microsphere composites(defined as C@HAp/Arg) obtained promptly via a one-step mild hydrothermal method, was applied to remove U(Ⅵ) from aqueous solutions. Based on the characterization of transmission electron microscopy(TEM), scanning electron microscopy(SEM), Fourier transformed infrared spectroscopy(FT-IR), X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS), the synthesized C@HAp/Arg presented globular morphology and abundant functional groups(e.g., —COO^-), which were beneficial to its combination with U(Ⅵ). The interaction mechanism and removal capability of U(Ⅵ) on C@HAp/Arg were studied by batch adsorption technique and spectroscopy analysis. The results implied that U(Ⅵ) can form strong surface complexes on C@HAp/Arg. The kinetics adsorption of U(Ⅵ) followed pseudo-second-order kinetic model with high removal efficiency($95% within 5h at pH 5.0). The adsorption isotherms were well fitted by Langmuir model, implying that U(Ⅵ) uptake on C@HAp/Arg was monolayer coverage. It was found that the maximum adsorption capacities of CSs, C@HAp and C@HAp/Arg toward U(Ⅵ) were calculated to be 23.16,72.09 and 569.66 mg/g, respectively, at 298.15 K and pH 5.0, and thermodynamic parameters revealed that the adsorption processes of U(Ⅵ) were spontaneous and endothermic. In addition, effect of co-existed ions and CO_3^(2-)concentrations demonstrated that U(Ⅵ) adsorption on C@HAp/Arg was weakly interfered by foreign ions and carbonate concentrations. More importantly, the adsorption performance of U(Ⅵ) on C@HAp/Arg was still over $87% after five cycles. Therefore, it was noted that the versatile C@HAp/Arg could be potentially used as a powerful building block for the enrichment and disposal of U(Ⅵ) from aqueous solutions, which could efficiently reduce the potential toxicity of U(Ⅵ) in the U(Ⅵ)-contaminated water.

Flavanols from the Camellia sinensis var.assamica and their hypoglycemic and hypolipidemic activities

α-Glucosidase and lipase inhibitors play important roles in the treatment of hyperglycaemia and dyslipidemia. To identify novel naturally occurring inhibitors, a bioactivity-guided phytochemical research was performed on the pu-erh tea. One new flavanol, named(–)-epicatechin-3-O-(Z)-coumarate(1), and 16 known analogs(2–17) were isolated from the aqueous extract of the pu-erh tea. Their structures were determined by spectroscopic and chemical methods. Furthermore, the water extract of pu-erh tea and its fractions exhibited inhibitory activities against α-glucosidases and lipases in vitro;compound 15 showed moderate inhibitory effect against sucrase with an IC_(50) value of 32.5 μmol/L and significant inhibitory effect against maltase with an IC_(50) value of 1.3 μmol/L. Compounds 8, 10, 11 and15 displayed moderate activity against a lipase with IC_(50) values of 16.0, 13.6, 19.8, and 13.3 μmol/L,respectively.

Numerical study on structure of meso-β scale rainstorm system during IOP523 of HUAMEX

One of the scientific goals of HUAMEX (Torrential Rainfall Experiment over Both Sides of the Taiwan Strait and Adjacent Area), a special project in the National '863' Scientific Project, is to reveal meso-β scale structure of heavy rainfall. However, limited by the observational instruments, the resolution of the data attained from the outfield scientific observation network cannot reveal the meso-β scale structure. A 36-h numerical simulation of heavy rainfall case from May 23 to May 24, 1998 during IOP523 of HUAMEX was performed by the mesoscale numerical model of PSU/NCAR MM5, and the meso-p scale structure of con-vective system was examined based on the model output in this note. The results point out that the meso-β scale features of the heavy rainfall are clear considerably at low, middle and upper levels, respectively. There is a strong ageostrophic feature between the geopotential height field and the wind field on the upper level. The vertical cross sections of 54 km coarse grid and 18 km

A ternary mechanism for the facilitated transfer of metal ions onto metal–organic frameworks: implications for the "versatility" of these materials as solid sorbents

Although metal–organic frameworks offer a new platform for developing versatile sorption materials,yet coordinating the functionality,structure and component of these materials remains a great challenge.It depends on a comprehensive knowledge of a“real sorption mechanism”.Herein,a ternary mechanism for U(Ⅵ)uptake in metal–organic frameworks was reported.Analogous MIL-100s(Al,Fe,Cr)were prepared and studied for their ability to sequestrate U(Ⅵ)from aqueous solutions.As a result,MIL-100(Al)performed the best among the tested materials,and MIL-100(Cr)performed the worst.The nuclear magnetic resonance technique combined with energy-dispersive X-ray spectroscopy and zeta potential measurement reveal that U(Ⅵ)uptake in the three metal–organic frameworks involves different mechanisms.Specifically,hydrated uranyl ions form outer-sphere complexes in the surface of MIL-100s(Al,Fe)by exchanging with hydrogen ions of terminal hydroxyl groups(Al-OH_(2),Fe-OH_(2)),and/or,hydrated uranyl ions are bound directly to Al(Ⅲ)center in MIL-100(Al)through a strong inner-sphere coordination.For MIL-100(Cr),however,the U(Ⅵ)uptake is attributed to electrostatic attraction.Besides,the sorption mechanism is also pH and ionic strength dependent.The present study suggests that changing metal center of metal–organic frameworks and sorption conditions alters sorption mechanism,which helps to construct effective metal–organic frameworks-based sorbents for water purification.

Designed assembly of heterometallic cluster organic frameworks based on Th_6 cluster

Four novel compounds based on hexanuclear thorium cluster were synthesized and characterized.Compound 1[Th_(6)(HPy C)_(8)(HCOO)_(4)]is formed by replacing formate ligands of preassembled thorium cluster[Th_(6)O_(4)(OH)_(4)(H_(2)O)_(6)(HCOO)_(12)]with eight H_(2)Py C(4-pyrazolecarboxylic acid)under solvothermal conditions.Each of the HPy C^(-)ligands is coordinated with one Cu^(2+)to form the(4,8)-connected scu-net structure of compound 2[(Cu Cl_(2))_(2)Th_(6)(HPy C)_8(HCOO)_(4)].In compound 3[(Cu Cl_(2))_(2)Th_(6)(HPy C)_(10)(HCOO)_(4)],ten of the formate ligands of preassembled Th_(6)cluster are replaced by HPy C^(-)ligands.Compared with compound 2,the two extra HPy C^(-)ligands in the equatorial plane of the Th_(6)cluster in compound 3 are not further connected to copper ions.Therefore,the topology structure of compound 3 is same with that of compound 2.Compound 4[(Cu_(3)Cl_(2))(Cu Cl_(2))Th_(6)(Py C)_(3)(HPy C)_(4)(HCOO)_(5)]contains three kinds of metal nodes,Th_(6)cluster,Cu_(3)cluster and mononuclear Cu^(2+),and exhibits a novel(5,7)-connected net structure,which was first discovered in actinide MOFs.Furthermore,considering the satisfactory stability of compound 4 and its unsaturated metal nodes and Lewis acid sites,the catalysis of cycloaddition of CO_(2)was further studied.We found that this thorium-copper heterometallic cluster organic framework can be used as a potential actinide functional material for catalyzing the efficient CO_(2)conversion to value-added products.