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To study the seismic failure mechanism of Plate-Shell Integrated Concrete Liquid Storage Structure (PSICLSS), the mechanical properties of each component under earthquake are studied. The influences of excitation frequency and amplitude on seismic responses of PSICLSS are analyzed. Based on the alternate load path method, the influences of partial component failure on the seismic responses of PSICLSS are studied, and the effects of free surface and structure size on seismic responses of PSICLSS are studied. Results show that the upper connection beams, upper plate and upper shell are easily tension failure. The effect of external liquid sloshing on the seismic response of the structure is more significant. The upper beams have a more significant influence on the structural seismic response. Considering the liquid free surface will cause structural stress increases. With the increase of the structural size, the structural stress, displacement and hydraulic pressure all increase, but the liquid sloshing height does not increase as the structural size increases.

Soil carbon is a crucial component of the global carbon cycle, and carbon mineralization is influenced by various factors. However, there is a lack of systematic analyses on the responses of carbon mineralization in different soil types to the addition of exogenous organic matter. This study investigates the effects of compost addition on the mineralization and kinetic characteristics of soil carbon across three typical agricultural soils: paddy soil, black soil, and cinnamon soil. A 210-day incubation study was conducted with four treatments: Control (un-amended soil), R (soil + straw), R1M (soil + straw + low compost application rate), R2M (soil + straw + high compost application rate). The results showed that the CO2 emission rates of the three soils were higher during the early stage (1–37 days) and decreased afterward. The CO2 emission rates of the paddy soil and the black soil were significantly higher than those of the cinnamon soil. The addition of compost significantly increased both the CO2 emission rate and the cumulative release of CO2, especially in the R2M treatment. At the end of the incubation, the SOC contents were higher in the R2M treatment than in the Control for all three soils (p < 0.05), with the most notable increase in the cinnamon soil (60.93%). Compost addition significantly enhanced the active carbon pool (Ca), slow carbon pool (Cs), and potentially mineralizable carbon pool (Cp), while decreasing the mineralization rate (ka) of the Ca, but the effect on the mineralization rate (ks) of the Cs and mineralization entropy (Cm) varied by soil types. The ks of the paddy soil was significantly reduced by 23.08% under the R1M and R2M treatments compared with the Control and R treatment. The ks of the black soil was significantly increased by 59.52% under the R2M treatment compared with the Control. The ks of the cinnamon soil was elevated considerably by 79.31% under the R2M treatment compared with the Control, R, and R1M treatments (averaging 0.29 × 10−2 d), and the ks of the paddy soil and black soil were significantly higher than those of the cinnamon soil under the R2M treatment. The Cm was significantly higher in the organic material added treatments than in the Control for the black soil and the paddy soil, but showed a higher value in the R treatment than in the R2M and Control for the cinnamon soil. In conclusion, compost addition stimulated soil carbon mineralization and improved the SOC content, especially in the cinnamon soil, while reducing the mineralization rate of the active carbon pool across the three soils. The mineralization rate of the slow carbon pool and the changes in mineralization entropy were dependent on soil types, primarily related to the initial soil nutrient contents, pH, and particle compositions. These findings offer valuable insights for managing the soil carbon pool in agricultural ecosystems.

To discriminate the transport characteristics of residue-derived carbon (Cres) from soil native carbon (Csoil) in black soil with split nitrogen application, a 540-day incubation study was conducted with four treatments: Control (unamended soil), R (soil + residue), RN1 (soil + residue + one-time application of nitrogen fertilizer), and RN3 (soil + residue + three-time application of nitrogen fertilizer). The total soil organic carbon (TOC) of the incubated soil was separated into three fractions: light fraction (LF), occluded-particulate organic matter fraction (OPOM), and heavy fraction (HF). The results showed that the TOC content was significantly higher in the RN1 and RN3 (averaging 20.77 g/kg) than in the R (18.43 g/kg) and Control (19.03 g/kg) after 540 days. Nitrogen fertilization significantly increased the residual rate of HF−Cres by 11.75% (p < 0.05), and the RN3 treatment significantly increased the residual rate of OPOM−Cres by 18.84% (p < 0.05) and reduced the loss rate of LF−Csoil by 77.01% (p < 0.05) compared with the R treatment. The soil catalase activity declined continuously along with incubation and was higher in the RN3 treatment than in the RN1 treatment after 180 days. The correlation analysis showed that the LF−Csoil and −Cres, as well as the HF−Csoil and catalase activity, were the main contributors to the TOC. Conclusively, nitrogen application, especially split nitrogen application, could stimulate the ability of soil to retain exogenous carbon and preserve native carbon.

We introduce a topology optimization method for the stiffness-based design of structures made of plates. Our method renders topologies made distinctly of plates, thereby producing designs that better conform to manufacturing processes tailored to plate structures, such as those that employ stock plates that are cut and joined by various means. To force the structural members to be plates, we employ the geometry projection method to project an analytical description of a set of fixed-thickness plates onto a continuous density field defined over a 3-dimensional, uniform finite element grid for analysis. A size variable is assigned to each plate and penalized so that the optimizer can entirely remove a plate from the design. The proposed method accommodates the case where the plates in the topology are rectangular and solid, and the case where the boundaries of the plates can change and holes can be introduced. The latter case is attained by composition with a free density field. We present examples that demonstrate the effectiveness of our method and discuss future work.

A 1.8 kb 5'-flanking region of the large subunit of ADP-glucose pyrophosphorylase, isolated from watermelon (Citrullus vulgaris S.), has fruit-specific promoter activity in transgenic tomato plants. Two negative regulatory regions, from -986 to -959 and from -472 to -424, were identified in this promoter region by fine deletion analyses. Removal of both regions led to constitutive expression in epidermal cells. Gain-of-function experiments showed that these two regions were sufficient to inhibit RFP (red fluorescent protein) expression in transformed epidermal cells when fused to the cauliflower mosaic virus (CaMV) 35S minimal promoter. Gel mobility shift experiments demonstrated the presence of leaf nuclear factors that interact with these two elements. A TCCAAAA motif was identified in these two regions, as well as one in the reverse orientation, which was confirmed to be a novel specific cis-element. A quantitative β-glucuronidase (GUS) activity assay of stable transgenic tomato plants showed that the activities of chimeric promoters harbouring only one of the two cis-elements, or both, were ~10-fold higher in fruits than in leaves. These data confirm that the TCCAAAA motif functions as a fruit-specific element by inhibiting gene expression in leaves.

The purpose is to investigate the response of seepage field, displacement field and stress field in the surrounding rock mass during dynamic tunneling in soft soil area. Relied on a large-diameter river-crossing shield tunnel project, considering driving force, shield tail grouting pressure, and the friction resistance between the shield shell and the soil, a three-dimensional fine tunnel model considering the liquid-solid coupling effect in the soil during dynamic tunneling was established by employing the finite difference method. The response characteristics of pore water pressure, displacement and stress in the surrounding rock mass were obtained. The results show that during shield tunneling and shield tail grouting, the pore water pressure in the range of 0.5 times the hole diameter around the tunnel decreases and increases respectively due to the liquid-solid coupling in the surrounding rock mass. When the shield tunneling moves away, the pore water pressure of the soil near the vault decreases, and the pore water pressure near the tunnel arch bottom increases. The impact range of shield tail grouting on the vertical settlement of the upper soil is about 0.5 times the hole diameter. The shield tail grouting can effectively reduce the vertical settlement of the top soil and slow down the vertical uplift of the bottom soil. During shield tunneling the vertical stress distribution of the soil above the vault of the working position and around the excavation surface is funnel-shaped, and the vertical stress around the excavated tunnel decreases.

With the development of production living standards and water treatment technology, the height of aboveground liquid storage structures has increased and the cross-sections have become complex; therefore, it is necessary to evaluate the seismic performance of aboveground concrete liquid storage structures with increased heights and complex cross-sections. In this paper, 6 long-period ground motions and 6 common ground motions are selected and the time-domain and frequency characteristics are analyzed. The dynamic response of a high liquid level plate-shell integrated concrete liquid storage structure (PSICLSS) to long-period ground motion is studied. The results show that ground motion does not cause intense shaking of the liquid at the bottom of the storage structure. Under the action of long-period ground motion, the sloshing height of the liquid will be far higher than the design dry string height, but it will not cause damage to the structural components. Under the action of common ground motion, the sloshing height of the liquid meets the design requirements, but rare earthquakes will cause local damage to the PSICLSS.

Structural shapes that can be described by geometric primitives such as bars and plates are commonly encountered in mechanical, aerospace and civil structures. In this thesis, I determine the optimal layout of a set of geometric primitives within a design envelope using topology optimization techniques. To perform the structural and sensitivity analyses of these structures, the geometric primitives are mapped onto a continuous density field defined over a fixed finite element grid via the geometry projection method. As a result, the optimal topology can be more easily fabricated by joining stock structural shapes through various means. Previous works on geometry projection methods only consider minimum compliance for structures made of bars. In this thesis, I formulate topology optimization techniques to design plate structures, and to consider other important structural and manufacturing considerations such as strength, as well as the placement of the primitives to avoid impractical cuts and to ensure a minimum separation between them. I also develop numerical techniques to improve the efficiency and the effectiveness of the proposed methods so that they can be employed in the design of realistic-size problems and to systematically find better local optima.

By identifying antibiotics that had the least phytotoxic effects on explants during genetic transformation, we evaluated the effect of various antibiotics on callus induction and morphogenesis from leaf explants and in vitro growth of Fragaria  ×  ananassa Duch. cv. Toyonaka. Results showed that kanamycin (Kan) significantly inhibited callus induction, bud differentiation and root morphogenesis while carbenicillin (Carb), cefotaxime (Cef) and an equal concentration of Cef and Carb up to 500 mg L −1 had no significant effects on callus induction and shoot growth. Kan, even at 2.5 mg L −1 , significantly inhibited callus induction, shoot regeneration and root formation, while no shoots regenerated at concentrations above 15 mg L −1 . Rooting was completely inhibited in the presence of 50 mg L −1 Kan. Cef had negative effects on shoot regeneration from leaf explants and in vitro growth of strawberry. Compared to Cef, Carb at ≤300 mg L −1 significantly promoted shoot and root organogenesis. However, an equal concentration of Carb plus Cef could alleviate the negative effect of Cef on strawberry. Results from relative electrolyte leakage, root and antioxidant activities, O 2 ·− production rate, H 2 O 2 , proline and MDA contents showed that Kan, Cef and Carb caused electrolyte leakage and triggered active enzymatic processes and metabolism. This offers a possible mechanism for the inhibition or stimulation of strawberry growth caused by these antibiotics.