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The effect of heat treatment process on the microstructure and properties of 140 ksi grade In718 alloy was studied. The solid solution temperature adopted three temperatures： 1 023 ℃， 1 030 ℃ and 1 050 ℃， and the aging temperature adopted three temperatures： 760 ℃， 780 ℃ and 800 ℃， the total of 9 sets of experimental data were cross tested. Then the alloy samples after different heat treatment processes were tested for room temperature tensile， -60 ℃ Charpy V-notch impact ， hardness， grain structure and other indicators， and analysis of the fracture structure and precipitates were analyzed. Research has shown that as the solid solution temperature increases， the strength of In718 alloy decreases， the plasticity and toughness increase， the grain size increases and δ phase decreases； At the same solid solution temperature， as the effective temperature increases at any time， the strength of In718 alloy decreases and the plasticity and toughness increase. The aging temperature has no effect on the grain size. γ″phase gradually coarsens from granular and spherical to needle like， and the number of γ″phases also shows a decreasing trend. Among them， the comprehensive performance of alloy is the best after solid solution treatment at 1 023 ℃ and aging treatment at 760 ℃， and the matching of indicators such as tensile strength， yield strength， plasticity， and impact toughness reaches the best level.

For improving the corrosion resistance of 904L stainless steel under high Cl- concentration environment with different pH values condition，the corrosion behavior of 904L austenitic stainless steel in 100 g/L NaCl solution at different pH values was studied by cyclic polarization curves，electrochemical impedance spectroscopy，Olympus confocal microscopy，scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).Results showed that the corrosion resistance of 904L stainless steel increased with the increase of pH value，EIS consisted of two capacitive reactance arcs，and the radius of capacitive reactance arc increased with the increase of pH value，and the capacitive reactances were all in the same order of magnitude.Meanwhile，lower pH value conditions could enhance the destructive effect of Cl- on the passive film.With the decrease of pH value，the range of passive region of the material decreased.When the pH＝2，slight pitting occurred on the surface of the material.

Millet was treated at 600 MPa for 15 min and 30 min, respectively (millet: water=1∶1 or 1∶2 (w/w). The effects of different treatment conditions on physicochemical and functional properties of millet flour were investigated to provide a theoretical basis for optimizing the quality characteristics of millet powder. The results showed that high hydrostatic pressure (HHP) treatment affected the morphology, particle size, and crystal characteristics of the four different millet powders. The morphology of starch particles in the whole flour changed from a scattered irregular sphere to complex and bonded to block structure with other substances, and the average particle size decreased significantly. The overall particle size shrank, and the crystal structure changed from natural A type to B type. The effect on the microstructure was particularly significant when the ratio of millet to water was 1∶2. The dynamic rheological tests showed that Gʹ and tanδ of millet paste after HHP treatment were higher than those of original powder, and Gʺ was lower than that of original powder. The results showed that HHP treatment could improve the elasticity and viscosity of millet starch, and this technology could be used as an effective physical modification method to improve the physical properties of millet powder.

Aiming at the problems of pressure - bearing pipes thinning and even rupture caused by the high temperature corrosion of the biomass boiler superheaters, the microstructure and properties of superheater tube wall after service were analyzed based on working environment. Research results showed that elements such as Cl and alkali metals in the flue gas underwent a series of complex physical and chemical reactions with the heating surface in the form of gas, solid and liquid phases at high temperatures, resulting in the corrosion of the superheaters pipe wall. The fly ash was deposited on the metal surface and soakably adhered to the oxide layer, which made the oxide protective layer on the pipe wall surface fell off, leading to the thinning of the pipe wall. Meanwhile, the service temperature of the high temperature superheaters was higher than that of the medium temperature superheater, and the corrosive peeling of its oxide layer was more serious. After long - term service, the micro hardness and tensile property of the pipe wall of the high temperature superheater after corrosion was decreased, compared with that of the medium temperature superheater. But, both of them still met the standard requirements and service conditions. Therefore, taking appropriate protective measures was able to prevent further corrosion and thinning of the pipe wall, which could shorten the maintenance period and reduce operating costs.

This experiment explored the effects of fermentation time and temperature on polyphenol content in millet sour congee fermentation, and further compared the differences of main components between millet sour congee and millet congee. The results showed that the content of polyphenols in millet sour congee increased with time, and reached the maximum at 20 h. At the fermentation temperature of 32 ℃, the content of polyphenols in millet sour congee was the highest. Compared with millet congee, millet sour congee reduced the polyphenol loss caused by cooking, and the antioxidant activity of polyphenols in sour congee was higher than that of millet congee. The contents of protein and fat in millet sour congee were higher, reaching 13.5 mg/100 g and 6.2 mg/100 g respectively, while the starch content (53.4 mg/100 g) was 8.7 mg/ 100 g lower than that of Millet Congee. In addition, the fermentation of sour congee also increased the content of insoluble dietary fiber and the content of free tryptophan in the supernatant. This study provides theoretical support for further research and development of millet sour congee related dietary food.

Aim: To identify subtypes of job crafting among Chinese nurses and to explore the characteristics of different subtypes and their relationship with work engagement. Design: A cross‐sectional study. Methods: A survey of 350 clinical nurses was conducted between December 2022 and January 2023. Identify profile categories for nurses' job crafting using a latent profile analysis. Logistic regression and ANOVA were used to explore the characteristics of different categories of nurses' job crafting in terms of sociodemographic, work engagement variables. Results: Ultimately 3 latent profiles are identified: low job crafting (Class 1, N = 177, 50.7%), moderate job crafting (Class 2, N = 136, 38.9%), high job crafting (Class 3, N = 37, 10.5%). Nurses who are female, aged 31 to 40 and married are more likely to be grouped into Class 2. Nurses with a middle level of title are more likely to be grouped as Class 3. Nurses with high levels of work engagement are more likely to be grouped as Class 2 and Class 3 rather than Class 1. Conclusion: The job crafting has a distinctly classified character among Chinese nurses. 89.6% of nurses were at a low to medium level of job crafting, work engagement is an important predictor of nurses' job crafting. Nursing Managers should focus on the low job crafting group and develop targeted interventions to help nurses improve their job crafting and work engagement levels. Patient or Public Contribution: None. [ABSTRACT FROM AUTHOR]

Aim: To determine whether social support and psychological resiliency are significant mediators of the associations between risk perception and quality of working life in Chinese nurses working with infectious diseases. Design: A cross‐sectional study. Methods: A cross‐sectional survey of 879 nurses in infectious diseases department of specialty or general hospitals in China completed online questionnaires on the nurses' risk perception questionnaire, quality of working life, psychological resilience and the social support rating scale. Results: Our study observed that risk perception directly negatively influences the quality of working life of infectious disease nurses, while psychological resilience and social support positively chain mediate this relationship. Conclusion: Critical elements impacting the quality of working life of infectious disease nurses are risk perception, psychological resilience and social support. Managers may think about decreasing the level of risk perception and enhancing the quality of working life of infectious disease nurses by enhancing their psychological resilience and providing support. Public Contribution: The quality of working life of infectious disease nurses should be a priority for nursing management; it is critical to maintain their health and well‐being, raise the quality of care and lower turnover. Managers should create resilience‐building programmes and support tools to assist nurses properly perceive risks and adopt protective strategies to deal with them to improve the quality of working life for nurses. [ABSTRACT FROM AUTHOR]

The experiment was to study the effect of replacing soybean meal with different proportions of whole plant fermentated hybrid tree on growth performance, carcass traits, meat quality and nutrient apparent digestibility of finishing pigs. A total of 48 healthy 'Duroc x Landrace x Yorkshire' crossbred finishing pigs with an initial weight of (60.44±2.51) kg were randomly divided into four groups, with three replicates in each group and four pigs in each replicate. The finishing pigs in group A (control group) were fed with basal diet, and the finishing pigs in group B, group C and group D were fed with experimental diet with 3%, 5% and 7% whole fermented hybrid tree instead of soybean meal, respectively. The pre-test lasted for 10 d, and the formal test lasted for 45 d. The results showed that compared with group A, the average daily gain of finishing pigs in group B was increased by 2.78% (P>0.05), the eye muscle area, intramuscular fat content and protein content of finishing pigs in experimental groups were significantly increased (P<0.05). The apparent digestibility of acid detergent fiber, crude fat, neutral detergent fiber, calcium and phosphorus in diets of finishing pigs in group C and group D were significantly increased (P<0.05). The experiment indicates that using 3% whole plant fermented hybrid tree instead of soybean meal has better effect on growth performance, meat quality and apparent digestibility of finishing pigs. [ABSTRACT FROM AUTHOR]

A self-healing group key distribution scheme with revocation in MANET using dual directional hash chain was proposed.The association relation between different session keys was built.By means of broadcast information and own secrets,the legal nodes which lost some legal session keys due to network faults could be capable of recovering such lost session keys on their own,without requiring additional transmission from the group manager.The group manager could revoke the group nodes by revocation polynomial.Node was endowed with a set of masking secret according to its life-cycle.Through the security and efficiency analysis,the key distribution scheme reduces communication cost and storage cost yet still achieves security property.

In order to investigate the insufficiency of target sampling in current network topology measurement practice and the distortion of measurement models,a sort of target sampling methods based on routing behavior analysis were pre-sented,namely,the uniform random sampling as a benchmark method,the minimum cover sampling as an optimal method,the last-hop sampling for the path diversity,and the bisection sampling for the destination prefix diversity.Ex-periments based on real measurement data show that a half of topology information can be missed in the traditional ‘1 per /24’ random sampling,of which 10% of missed information is caused by the path diversity and the rest is caused by des-tination prefix diversity.The minimum cover sampling is robust to the routing dynamics and performs better than the uniform random sampling at the long-term practice.

Through deeply analyzing on the principle,mode,character of DoS,and the DoS attack faced by SIP network,combining with the idea of Client Puzzle,DFA,long-distance linkage,host linkagethe,the character of SIP network,and the principle of SIP proxy server,the defence model of SIP proxy server for DoS attack was put forward,and the testbed to test the ability of this model to resist DoS attack was designed.The experiment result proves that this model can effectively resist the DoS attack for SIP proxy server with millisecond delay of signal transfer,and improves the usablity of SIP network.

A new self-healing key distribution scheme of MANET based on sliding window was proposed in order to re-duce the burden of manager supervising self-healing MANET and to deal with the scene of some users’ lifetime bestrid-ing two session windows.A dual hash directional key chain model was set up.The model achieves t-revocation capability by using control parameter.Through the security analysis,the model has settled users’ bestriding problem yet still achieved security property.Because manager once distributes initial private information to bestriding user and so avoids distributing it again in rebuilding phase,the model reduces the communication cost.

To build the prospect of Chinese IP-level topology,the traditional destination sampling method was evaluated;three new improved techniques were developed;and Chinese network was measured.With the methodology of complex network,the topology characteristics were extracted and compared.The sizes of autonomous systems（AS） were investi-gated with the IP2AS technique.The results showe that lots of information is missed by the traditional method;the load is reduced to about a half by the new techniques while the completeness is retained;and the size of new discovered Chinese topology is 5 times as many as that discovered by CAIDA’s skitter.Compared to skitter’s topology,the more complete topology showe more observable dissortativity,weaker clustering,shorter distance and more disequilibrium of node traf-fic distribution.The heavy-tailed distribution of AS sizes is discovered.

To construct attack scenarios and predict intrusion intents automatically,a real-time alert correlation approach based on capability transition model was proposed.By highly abstracting the reasoning evidences,the process complexity is effectively reduced.Experiment results on the DARPA2000 IDS test dataset indicate that the method is effective and efficient.

A new key management framework was proposed based on mutual identity authentication in elliptic curve field.Threshold scheme enhances system more stable.Mutual identity-based authentication guarantees node to communicate with the right one,by which the malicious nodes aiming to fake or send false information can be drawn away from MANET.

Through analyzing the security of SIP,combining PKI technology,digital time authentication,digital certifi-cate and the characteristic of SIP network,the safe communicated model of SIP network based on improved SIP protocol was put forward.New call established protocol was constituted used the primary flow for reference,new register protocol and roam register protocol were constituted,time synchronization protocol and negotiating key protocol was added for this model,and test the safe communicated model in real circumstance.The result of the experiment proved that this model improved the confidentiality,integrality,usability,non-repudiation and novelty of the SIP network with the millisecond delay which can be accepted.

A fundamental requirement for any network simulation environment is the realistic forwarding of packets from a source to a destination in the simulated topology.The routing decisions will be affected by topology changes.In almost all current simulators,all the nodes know the topology changes instantaneously,which is obviously unrealistic.The model of dynamic routing was presented and analyzed.Further an approach was proposed to compute the time needed for each node to know the topology changes,and dynamic MTreeNix routing mechanism was presented,which maintains static routing table and a message queue of topology changes,and looks up routing states according to the known time of different changes.Experimental results show that our approach can improve the realism of dynamic routing in network simulation,with high simulation efficiency.