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Nanomaterials have received increasing attentions owing to their potential hazards to the environment and human health; however, the multi-generational toxicity of graphene oxide under consecutive multi-generational exposure scenario still remains unclear. In the present study, Caenorhabditis elegans as an in vivo model organism was employed to explore the multi-generational toxicity effects of graphene oxide and the underlying mechanisms. Endpoints including development and lifespan, locomotion behaviors, defecation cycle, brood sizes, and oxidative response were evaluated in the parental generation and subsequent five filial generations. After continuous exposure for several generations, worms grew smaller and lived shorter. The locomotion behaviors were reduced across the filial generations and these reduced trends were following the impairments of locomotion-related neurons. In addition, the extended defecation cycles from the third filial generation were in consistency with the relative size reduction of the defecation related neuron. Simultaneously, the fertility function of the nematode was impaired under consecutive exposure as reduced brood sizes and oocytes numbers, increased apoptosis of germline, and aberrant expression of reproductive related genes ced-3, ced-4, ced-9, egl-1 and ced-13 were detected in exposed worms. Furthermore, the antioxidant enzyme, SOD-3 was significantly increased in the parent and filial generations. Thus, continuous multi-generational exposure to graphene oxide caused damage to the neuron development and the reproductive system in nematodes. These toxic effects could be reflected by indicators such as growth inhibition, shortened lifespan, and locomotion behavior impairment and induced oxidative response.

In the process of modern mechanical parts production, such as parts surface dust, metal powder, coating will appear "nodules" and "burr", easy to fall off small pit of coating surface. So, to ensure the quality of electroplating products plating, to carry out the study on substrate surface treatment before plating technology of plating is very meaningful.

The digital design of mechanical products is usually first reference existing parts, drawings, and experience to make original design data and design requirements, according to the design of digital model is set up, after an analysis of the finite element model according to the analysis results contrast design goal to design or structure parameter changes, to the expected design purpose. Analysis of the product is an essential part of product design.

Based on equations of gas diffusion equilibrium, a new design method, along with a CAD software package, was developed to improve the efficiency of fruit packaging design. Take guava fruit as a case study, the method we developed was used to calculate unknown pack parameters and simulate the dynamic change of in-pack gas concentrations. When the ratio of headspace and fruit volume was 2.5:1, it expended about 200 h before the equilibrium gas exchange was created. However, in the case of 0.3:1 ratio, it needed only 30 h to obtain the equilibrium state. Simulation results are useful for achieving high quality of package design, especially in the case of long transport distance or long-time storage.