Research on Contribution Rate of Independent Innovation to Economic Growth: Evidence from Changshou District of Chongqing City in China

Using the data of Chongqing Statistical Yearbooks from 2015 to 2020 and based on the Cobb-Douglas production function of Solow residual method, this paper constructs a functional relationship model among GDP, employment number, fixed asset investment, and economic growth. The contribution rate of independent innovation in Changshou District of Chongqing City is improved by using polynomial distributed lag model. Besides, the contribution rate of independent innovation in Shapingba District, Yuzhong District, Jiangbei District, and Beibei District of Chongqing City is compared with that in Changshou District. The research shows that, overall, independent innovation contributes a lot to the economic growth of Changshou District, but its contribution rate is in a slowly declining state. The government needs to take active measures to improve the level of independent innovation and promote the regional economic growth.

Experimental Study on Stiffness Softening of Soil-Rock Mixture Backfill under Metro Train Cyclic Load

Due to the thick soil layer, short backfill time, and low degree of consolidation of the soil-rock mixture backfill in Chongqing city, metro train tunnels passing through this type of strata are prone to large settlements during operation, which greatly affects the stability of the tunnel and the safety of metro train operations. In response to this problem, the dynamic triaxial test of the soil-rock mixture backfill under cyclic loading was carried out to study the dynamic characteristics of the soil-rock mixture backfill under cyclic loading. The effect of initial consolidation degree, effective consolidation confining pressure, and rock content on the stiffness softening of soil-rock mixture backfill was analyzed. The results show that the initial consolidation degree, effective consolidation confining pressure, and rock content are all important factors affecting the stiffness of soil-rock mixture backfill under cyclic loading. As the number of cycles increases, the lower the initial consolidation degree and effective consolidation confining pressure, the faster the attenuation of the softening index, and the larger the amplitude. As the rock content increases, the softening index increases and the stiffness of the backfill changes from softening to hardening. Based on the test data, the softening-hardening model of the soil-rock mixture is established, which is in good agreement with the field test results. This study can provide a reference for predicting and controlling the postconstruction settlement of the metro tunnel in the soil-rock mixture backfill.

Formation and Failure Mechanism of the Xinfangzi Landslide in Chongqing City (China)

At 2:00 a.m. on 1 July 2020, after several days of continuous heavy rainfall, the Xinfangzi landslide occurred in Zhengping Village, Ganshui Town, Qijiang District, Chongqing City, China. The area of the landslide was about 3.85 × 104 m2 and the volume was about 71.22 × 104 m3. The Xinfangzi landslide can be defined as a push-type landslide. Specifically, the main sliding area pushed the front squeezing area, causing it to slide laterally. The entire slip path of the landslide was a broken line, while the right edge and the front shear outlet position slipped loosely in a circular arc. In this study, finite element numerical calculations were used to compare and analyze the multisection plastic deformation of the landslide under natural and rainfall conditions based on field investigations. The formation and failure characteristics of the Xinfangzi landslide were further revealed. The results show that the cross and longitudinal sections of the landslide were in a critical state of instability under natural and rainfall conditions. A compound section was established along the slip path based on the cross and longitudinal sections. Due to the extrusion of the trailing edge of the landslide, the compound section’s leading edge was in a state of instability under natural conditions. Under rainfall conditions, the increase in the unit weight of the sliding mass was superimposed on the compound section, which amplified the thrust of the trailing edge and further accelerated the overall sliding process of the landslide. Based on the macroscopic deformation of the landslide, it was found that the sliding of the trailing edge of the landslide is the key factor promoting the failure of the front edge, and local slump is possible under rainfall conditions.

Seven new Otacilia Thorell, 1897 species from China (Araneae: Phrurolithidae)

Seven new species of Otacilia Thorell, 1897 from China are described and illustrated, all from both sexes: O. ensifera sp. nov. and O. arcuata sp. nov. from Hunan Province; O. spiralis sp. nov. from Hunan Province and Chongqing City; O. lubrica sp. nov. and O. wuli sp. nov. from Chongqing City; O. dentigera sp. nov. from Sichuan Province; and O. shanxi sp. nov. from Shanxi Province. Based on Jin et al. (2016), the seven new species described here belong to two species groups: O. ensifera sp. nov., O. shanxi sp. nov., O. spiralis sp. nov. and O. lubrica sp. nov. belong to the armatissima-group, while O. wuli sp. nov., O. dentigera sp. nov. and O. arcuata sp. nov. belong to the longituba-group.

Slope Belts of Paleouplifts Control the Pore Structure of Organic Matter of Marine Shale: A Comparative Study of Lower Cambrian Rocks in the Sichuan Basin

Extensive exploration of the marine shale of the Niutitang Formation in south China has been conducted. However, exploration and development results have varied considerably in different areas. For example, the Niutitang shale in Jingyan City (Southwestern Sichuan Basin) produces a large amount of gas with a long period of stable production. In contrast, most development wells in the Niutitang shale in Chongqing City do not produce gas. Scanning electron microscopy images showed that the organic matter (OM) pore development in the Niutitang shale in Jingyan is abundant, large in size, and are well connected. In contrast, OM pores in the Niutitang shale in Chongqing are rarely observed. OM pore development of the Jingyan and Chongqing shales is mainly controlled by thermal maturity as shown by equivalent vitrine reflectance determinations. The moderate thermal maturity has resulted in the development of a large number of OM pores in the Niutitang shale in Jingyan, whereas the high thermal maturity of the Niutitang shale in Chongqing has led to the destruction of most of the OM pores. Due to the existence of ancient uplift, the shale was buried shallowly in the process of hydrocarbon generation evolution, and the shale avoided excessive thermal evolution and retained appropriate thermal maturity. In the Jingyan area, due to its location near the central uplift in the Sichuan Basin, the Niutitang shale deposited nearby avoided excessive evolution, and a large number of OM pores were retained in the reservoir.

Newly Discovered Tuff in the Lower Shaximiao Formation in Yunyang, Chongqing, Southwestern China and Its Constraint on the Burial Age of the Yunyang Dinosaur Fauna

The Shaximiao Formation is one of the important Mesozoic burial horizons of dinosaur fossils in the Sichuan Basin. Although a large number of research results on the stratigraphic age of the Shaximiao Formation have been published, the age and division of the Shaximiao Formation are still controversial. To a certain extent, this affects the precise constraints on the burial age of the dinosaur fauna in Yunyang, Chongqing. In this study, the newly discovered tuff intercalation in the Lower Shaximiao Formation in Pu'an Township, Yunyang County, Chongqing City, was taken as the research object, and its lithology and formation age were determined using thin section identification, X-ray diffraction (XRD), scanning electron microscopy (SEM), and U-Pb zircon dating. The field observations and thin section microscopic characteristics of the rocks reveal that the clay rock intercalation has a typical sedimentary tuff structure, which is altered lithic tuff. The SEM imaging and XRD results indicate that it has a typical tuff mineral composition. The U-Pb zircon dating shows that the weighted average age of the newly discovered tuff is 174.8 ± 2.4 Ma, and the burial age of the dinosaur fossils is estimated to be 174.7 ± 2.4 Ma based on the sedimentation rate and the thickness of the stratum. Key words: Sichuan Basin; Shaximiao Formation; Yunyang Dinosaur Fauna; Tuff; Burial Age

Displacement Evolution of Reverse-Dip Rock Slope Considering the Change of the Reservoir Level

This paper investigates the toppling deformation characteristics of the displacement evolution in different portions for a reverse-dip rock slope, through a case study of Xiaodongcao slope in Chongqing city, China. Firstly, the elevation, slope angle, and aspect were obtained by the field survey, and then they were adopted in the partitioning process related to geological and geometrical conditions by the ArcGIS packages. Secondly, the spatiotemporal cloud map of the displacement was obtained by discrete monitoring data of surface displacement of the slope. Finally, the topping deformation was determined by superposing the cloud map of the displacement and the geometrical partition, considering the change of the reservoir level. The main findings are summarized as follows: (1) the horizontal displacement is close to the total one, meaning that the slope topping deformation is mainly in the horizontal orientation.(2) In the front and middle edges of the slope, the horizontal displacement is pronounced, which increases with the increase of the reservoir level and vice versa. The vertical displacement mainly occurs in the trailing of the slope, which increases when the reservoir level changes. (3) The area in relation to the strong superposed displacement increases with the variation of the reservoir level. The largest area of superposed displacement is distributed at medium gradient, low elevation and north aspect zones.

New species and new distributional record of the genus Broscosoma Rosenhauer, 1846 (Coleoptera, Carabidae, Broscinae) from China

Two new species of the genus Broscosoma Rosenhauer, 1846 are described from China: Broscosoma guoliangi sp. nov. from Fujian Province and Broscosoma qiului sp. nov. from Chongqing City, respectively. In addition, Broscosoma ribbei rougeriei Deuve & Tian, 2002 is newly recorded from Derung-Nu Autonomous County Gongshan, Yunnan Province, China.

Study on the Installation and Construction Technology of the Transfer Stairway on the Track Platform on Bridge—— Taking the Construction of the Jialing River Bridge in Zengjiayan of Chongqing City as an Example

The bridge deck on the Yuzhong side of Zengjiayan Jialing River Bridge is close to subway lines and light rail stations. It is necessary to set up transfer stairways on both sides of the bridge. The construction technology of installing and replacing with tunnel under special conditions is discussed to provide reference for bridge construction.