Search

The construction of Free Trade Zone (FTZ) is an important strategic initiative for China to build a new platform for comprehensive opening up and a new carrier for leading high-quality development. Based on SCM (synthetic control method) and DID (double difference method), the economic data of Shaanxi when the FTZ policy was not implemented (“counterfactual” simulation) are synthesized using quarterly economic panel data of 14 provincial regions from 2013 to 2019, and compared with the real data for analysis, in order to study the effect of the FTZ policy on Shaanxi’s economic The study finds that the impact of the FTZ policy on Shaanxi’s trade and consumption is not significant. The study finds that the FTZ policy has a significant enhancement effect on Shaanxi’s economic development and a significant promotion effect on trade, while the promotion effect on consumption is not significant. The innovation and features of this paper are two: firstly, based on the “counterfactual” simulation, the study investigates the growth effect of the FTZ policy on the regional economy in Shaanxi, and explores the mechanism of the FTZ policy affecting the regional economic growth from the perspective of trade and consumption, changing the existing studies which are only based on the analysis of the impact of the FTZ policy on the regional economy, without further exploring the mechanism of the impact. Secondly, the SCM and DID methods are used to evaluate the economic effects of the FTZ policy in Shaanxi, and the robustness of the research results is verified from multiple perspectives, such as replacement and pseudo-time.

Oriented antibody immobilization has been widely employed in immunoassays and immunodiagnoses due to its efficacy in identifying target antigens. Herein, a heptapeptide ligand, HWRGWVC (HC7), was coupled to poly(glycidyl methacrylate) (PGMA) nanospheres (PGMA-HC7). The antibody immobilization behavior and antigen recognition performance were investigated and compared with those on PGMA nanospheres by nonspecific adsorption and covalent coupling via carbodiimide chemistry. The antibodies tested included bovine, rabbit, and human immunoglobulin G (IgG), while the antigens included horseradish peroxidase (HRP) and β-2-Microglobulin (β2-MG). The nanospheres were characterized using zeta potential and particle size analyzers, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and reversed-phase chromatography, proving each synthesis step was succeeded. Isothermal titration calorimetry assay demonstrated the strong affinity interaction between IgG and PGMA-HC7. Notably, PGMA-HC7 achieved rapid and extremely high IgG adsorption capacity (~3 mg/mg) within 5 min via a specific recognition via HC7 without nonspecific interactions. Moreover, the activities of immobilized anti-HRP and anti-β2-MG antibodies obtained via affinity binding were 1.5-fold and 2-fold higher than those of their covalent coupling counterparts. Further, the oriented-immobilized anti-β2-MG antibody on PGMA-HC7 exhibited excellent performance in antigen recognition with a linear detection range of 0–5.3 μg/mL, proving its great potential in immunoassay applications. [ABSTRACT FROM AUTHOR]

Anomalously high-amplitude seismic reflections are commonly observed in deeply buried Ordovician carbonate strata in the Halahatang area of the northern Tarim Basin. These bright spots have been demonstrated to be generally related to effective oil and gas reservoirs. These bright spot reflections have complex geological origins, because they are deeply buried and have been altered by multi-phase tectonic movement and karstification. Currently, there is no effective geological model for these bright spots to guide hydrocarbon exploration and development. Using core, well logs, and seismic data, the geological origins of bright spot are classified into three types, controlled by karstification, faulting, and volcanic hydrothermal activity. Bright spots differing by geological origin exhibit large differences in seismic reflection character, such as reflection amplitude, curvature, degree of distortion, and the number of vertically stacked bright spots in the seismic section. By categorizing the bright spots and the seismic character of the surrounding strata, their geological origins can after be inferred. Reservoirs formed by early karstification were later altered by epigenetic karstification. Two periods of paleodrainage further altered the early dissolution pores. In addition, faults formed by tectonic uplift also enhanced the dissolution of the flowing karst waters. Some reservoirs were subsequently altered by Permian volcanic hydrothermal fluids.Des reflecteurs sismiques de haute amplitude sont couramment observes dans des strates carbonatees ordoviciennes profondement enfouies dans la region de Halahatang de la partie nord du bassin du Tarim. Il a ete demontre que ces reflecteurs saillants sont generalement associes a des reservoirs de petrole et de gaz. Ces reflecteurs ont des origines geologiques complexes puisqu'ils sont enfouis profondement et ont ete modifies par plusieurs phases de mouvement tectonique et de karstification. Il n'existe actuellement aucun modele geologique permettant d'utiliser ces reflecteurs pour orienter l'exploration et la mise en valeur d'hydrocarbures. Les origines geologiques de reflecteurs sont regroupees, a la lumiere de carottes, de diagraphies et de donnees sismiques, en trois types controles par la karstification, la formation de failles et l'activite hydrothermale volcanique. Les reflecteurs aux origines geologiques distinctes presentent d'importantes differences sur le plan de la sismique reflexion, comme leur amplitude, leur courbure, leur degre de distorsion et le nombre de reflecteurs empiles verticalement dans la coupe sismique. En categorisant les reflecteurs et le caractere sismique des strates qui les entourent, il est possible d'inferer leurs origines geologiques. Des reservoirs formes par une karstification precoce ont ensuite ete alteres par une karstification epige-netique. Deux periodes de paleo-ecoulement ont a nouveau modifie les pores formes par dissolution precoce. Des failles formees par le soulevement tectonique ont en outre accru la dissolution par les eaux karstiques en mouvement. Certains reservoirs ont par la suite ete alteres par des fluides hydrothermaux volcaniques permiens. [Traduit par la Redaction], IntroductionBead-like 'bright spot' reflections often appear on seismic sections across carbonate fracture-cave reservoirs, as a result of significant differences in acoustic impedance between the reservoir and the surrounding rocks. They [...]