Sizes of nuggets are often used to evaluate spot weld quality in production. This paper presents a neural estimator used to carry out non-destructive on-line analysis of spot weld quality in which trained ANN function...Sizes of nuggets are often used to evaluate spot weld quality in production. This paper presents a neural estimator used to carry out non-destructive on-line analysis of spot weld quality in which trained ANN functions to map dynamic resistance characteristics into sizes of spot weld nuggets and results confirm the validity of neural network for this type of application.展开更多
Our study investigated the effect of utiliz</span></span><span><span><span style="font-family:;" "="">ing</span></span></span><span><sp...Our study investigated the effect of utiliz</span></span><span><span><span style="font-family:;" "="">ing</span></span></span><span><span><span style="font-family:;" "=""> chicken</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">wings and dehydrated shellfish to produce chicken nuggets rich in protein, minerals and vitamins.</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">The proximate composition, nutritional value, physical and sensorial properties were evaluated. The different</span></span></span><span><span><span style="font-family:;" "="">ly</span></span></span><span><span><span style="font-family:;" "=""> prepared chicken nuggets </span></span></span><span><span><span style="font-family:;" "="">were </span></span></span><span><span><span style="font-family:;" "="">supplemented with dehydrated shellfish CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0%, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">2%, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">4% and CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6%. There was </span></span></span><span><span><span style="font-family:;" "="">a </span></span></span><span><span><span style="font-family:;" "="">significantly reduction </span></span></span><span><span><span style="font-family:;" "="">in </span></span></span><span><span><span style="font-family:;" "="">moisture and </span></span></span><span><span><span style="font-family:;" "="">an </span></span></span><span><span><span style="font-family:;" "="">increasing in protein content (<i>P</i> < 0.05) in all Chicken Nuggets (CN) in comparison to the control. Fat content was significantly higher in CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0% than CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">2%, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">4% and CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6%. Ash content was increasing with added dehydrated shellfish, while </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">reduction in carbohydrates and total calories of the different chicken nuggets were noticed with </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">significant gradual rise in pH values, TBA values showed no significant difference (<i>P</i> < 0.05) between chicken nuggets. Results showed that using dehydrated shellfish in preparing chicken nuggets caused a marked rise in its content of Ca, Fe, Na, K, Zn, Mg and Mn levels, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0% had the lowest concentration of all minerals, and had lower value</span></span></span><span><span><span style="font-family:;" "="">s</span></span></span><span><span><span style="font-family:;" "=""> of vitamins A, E and D but CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6% had higher value</span></span></span><span><span><span style="font-family:;" "="">s</span></span></span><span><span><span style="font-family:;" "=""> of vitamins A, E and D. Control Nuggets (CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0%) had the lowest value of yellowness and highest value of lightness but CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6% had </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">highest value of yellowness and, </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">lowest value of lightness. </span></span></span><span><span><span style="font-family:;" "="">The </span></span></span><span><span><span style="font-family:;" "="">redness had </span></span></span><span><span><span style="font-family:;" "="">a </span></span></span><span><span><span style="font-family:;" "="">slightly reduction. All samples showed slight changes in</span></span></span><span><span><span style="font-family:;" "=""> hardness, cohesiveness, springiness, gumminess and chewiness were noticed. </span></span></span><span><span><span style="font-family:;" "="">An </span></span></span><span><span><span style="font-family:;" "="">increase in WHC, pick-up, and cooking loss of chicken nuggets with dehydrated shellfish was noticed. Panelists accepted all prepared chicken nuggets and the chicken nuggets CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">4% had </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">highest score compared with other chicken nuggets prepared.展开更多
Pulsar glitches, i.e. the sudden spin-ups of pulsars, have been detected for most known pulsars.The mechanism giving rise to this kind of phenomenon is uncertain, although a large data set has been built.In the framew...Pulsar glitches, i.e. the sudden spin-ups of pulsars, have been detected for most known pulsars.The mechanism giving rise to this kind of phenomenon is uncertain, although a large data set has been built.In the framework of the starquake model, based on Baym ＆ Pines, the glitch sizes（the relative increases of spin-frequencies during glitches） △Ω/Ω depend on the released energies during glitches, with less released energies corresponding to smaller glitch sizes. On the other hand, as one of the dark matter candidates,our Galaxy might be filled with so called strange nuggets（SNs） which are relics from the early Universe.In this case collisions between pulsars and SNs are inevitable, and these collisions would lead to glitches when enough elastic energy has been accumulated during the spin-down process. The SN-triggered glitches could release less energy, because the accumulated elastic energy would be less than that in the scenario of glitches without SNs. Therefore, if a pulsar is hit frequently by SNs, it would tend to have more small glitches, whose values of ？？/？ are smaller than those in the standard starquake model（with larger amounts of released energy）. Based on the assumption that in our Galaxy the distribution of SNs is similar to that of dark matter, as well as on the glitch data in the ATNF Pulsar Catalogue and Jodrell Bank glitch table, we find that in our Galaxy the incidences of small glitches exhibit tendencies consistent with the collision rates between pulsars and SNs. Further testing of this scenario is expected by detecting more small glitches（e.g.,by the Square Kilometre Array）.展开更多
In order to utilize the iron resource effectively in red mud, a laboratory experiment based on the orthogonal method was carried out. Nuggets were gotten by directly reducing the carbon-bearing pellets of red mud and ...In order to utilize the iron resource effectively in red mud, a laboratory experiment based on the orthogonal method was carried out. Nuggets were gotten by directly reducing the carbon-bearing pellets of red mud and coal. The results showed that the strongest influencing factor is temperature, and the separation between liquid iron and slag is thoroughly. The nuggets can be gotten when the pellets, in which xC/xO is 1.6 and the basicity is 1.0, were maintained in 30 min at 1 400 ℃. The nuggets have a high TFe content which is higher than that in the hot metal produced in BF. It also has a low content of Si and Mn, but a high content of S and P. The main compositions of the slag are amorphous phase mainly containing SiO;and unreduced Fe;SiO;. Of course, a little reduced iron retains in it.展开更多
Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical pr...Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, C, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.展开更多
Affleck-Dine baryogenesis generated high baryon density in the early Universe. The baryon chemical potential enhanced the potential barrier and significantly reduced the decay rate of false vacuum, which decreased fro...Affleck-Dine baryogenesis generated high baryon density in the early Universe. The baryon chemical potential enhanced the potential barrier and significantly reduced the decay rate of false vacuum, which decreased from infinity at the critical end point to zero at the critical nucleation point. When the decay rate reached zero, the false vacuum of high baryon density quark matter was unlikely to decay and could persist over cosmological time scales. Therefore, primordial quark nuggets(PQNs) could form and survive in the early Universe as the seeds of compact stars. This new mechanism for the formation of PQNs is different from Witten's stable droplet of quark matter.展开更多
Petrography and mineral chemistry of Ca, Al-rich inclusions of Ningqiang carbonaceous chondrite are studied and the highly Re-Os fractionated Pt-metal nuggets in it is discovered. The refractory inclusions are classif...Petrography and mineral chemistry of Ca, Al-rich inclusions of Ningqiang carbonaceous chondrite are studied and the highly Re-Os fractionated Pt-metal nuggets in it is discovered. The refractory inclusions are classified into melilite-spinel-rich, and spinel-pyroxene-rich types. The former probably crystallized from melts, while the latter could be aggregates of the nebular condensates. The strong f ractionation between Re and Os suggests a pre-solar origin of the Pt-metal nuggets, which probably experienced various processes of formation and evolution before being captured by the refractory inclusions as indicated by the depletions of W and Mo.展开更多
This paper focuses on the effect of welding parameters on microstructure and tensile strength of joints welded by friction-stir welding(FSW).The effects of pin profile(threaded conical,non-threaded conical and triangu...This paper focuses on the effect of welding parameters on microstructure and tensile strength of joints welded by friction-stir welding(FSW).The effects of pin profile(threaded conical,non-threaded conical and triangular pin),tool rotational speed(800,1000,1250 and 1600 r·min^(-1))and welding speed(63,80,100 and 125 mm·min^(-1))on the mechanical and microstructural properties of joints welded in 5-mm 7075-T6 were investigated.The results depict that the pin profile has a major role in the shape and grain size of the weld nugget zone(WNZ).In other words,a wider weld nugget and a finer grain size by threaded conical pin are obtained in WNZ.The attained data of tensile tests show that the maximum ultimate tensile strength(UTS)belongs to the threaded conical pin which is attributed to a finer grain size generated in the weld nugget zone.Additionally,it is found that the tensile strength increases with the welding speed increasing,whereas rotational speed has a bilateral effect on the tensile strength.The microhardness tests show that the minimum hardness is obtained in the heat-affected zone(HAZ).展开更多
Chicken nugget is a comminuted meat product commonly prepared from spiced chicken meat and other ingredients. The tenderness of chicken meat lowers its firmness and mouth feel which may reduce acceptability of chicken...Chicken nugget is a comminuted meat product commonly prepared from spiced chicken meat and other ingredients. The tenderness of chicken meat lowers its firmness and mouth feel which may reduce acceptability of chicken nugget made from it. Thus, acceptability of chicken nugget could be harnessed when legume flour extenders are used along. Therefore, acceptability as well as quality of chicken nugget from different legume flours were evaluated. Soyabean, groundnut and cowpea flours were used as meat extenders for development of raw chicken nuggets and thereafter cooked for consumption. The quality of both raw and cooked legume flour extended chicken nuggets were assessed based on functional properties, sensory properties, proximate composition, amino acid content and shelf stability in terms of lipid peroxidation and microbial load. In their raw state, the legume flour extenders competed favourably with each other. Among all, soyabean flour extender maintained remarkable functional properties that transcend into significant (P < 0.05) yield of 86.93% of chicken nugget in comparison to the control (86.37%), groundnut (84.95%) and cowpea (84.50%). Upon cooking, all the legume flour extended chicken nuggets varied in their quality attributes. Apart from the high level of flavour and low microbial load, cowpea extended chicken nugget was of low quality based on the parameters evaluated in comparison with other legume flour extended chicken nuggets. Of interest, soyabean extended chicken nugget followed by groundnut extended chicken nugget were of good quality based on sensory properties, high crude protein and amino acid levels, low cholesterol content and lipid peroxidation value as well as low microbial load.展开更多
The objective of this study is preparation of new <b>nutritious</b> products from quail meat compared to other products prepared from chicken meat as control and commercial products which bought from super...The objective of this study is preparation of new <b>nutritious</b> products from quail meat compared to other products prepared from chicken meat as control and commercial products which bought from supermarket. The proximate composition, chemical, physical and sensorial properties were evaluated. The different products were prepared as sausage form quail meat (SQ), chicken meat (SC) and commercial (SCo), and, kofta from quail meat (KQ), chicken meat (KC) and commercial (KCo), and, nuggets from quail meat (NQ), chicken meat (NC) and commercial (NCo). The result observed that the chemical composition of products that prepared from quail meat recorded the highest content of protein and ash, on contrary, the lowest content of fat compared with products that prepare from chicken meat as control or commercial. All products that prepared from quail meat recorded high content of K, Ca, Mg, P, Fe, Zn, Se and vitamin A, Kofta was </span></span><span><span><span style="font-family:"">the </span></span></span><span><span><span style="font-family:"">highest one followed by nuggets then sausage products. While sausage products that prepared from both quail and chicken meat as control recorded the highest content of vitamin E, followed nuggets and kofta, respectively compared with commercial products. The results indicated decreasing cooking loss after preparing of quail meat products followed by both chicken meat products as control and commercial product</span></span></span><span><span><span style="font-family:"">, </span></span></span><span><span><span style="font-family:"">increasing water capacity (WHC)</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:"">of KQ and plasticity of SQ and NQ. All products were accepted from panelists while slightly significant difference among these products (P > 0.05). SC was the highest score in colour, taste, odour, texture and overall acceptability compared with SQ and SCo. Generally products were prepared from quail meat </span></span></span><span><span><span style="font-family:"">which </span></span></span><span><span><span style="font-family:"">showed high acceptance in sensory evaluation by panelists.展开更多
Components made by joining different materials are required in various engineering applications.Fabrication of suchcomponents is a challenging task due to the vast difference in mechanical,thermal and electrical prope...Components made by joining different materials are required in various engineering applications.Fabrication of suchcomponents is a challenging task due to the vast difference in mechanical,thermal and electrical properties of the materials beingused.Friction stir welding(FSW)is capable of joining dissimilar materials such as aluminum(Al)and copper(Cu)and thereforeresearchers have used this novel process for dissimilar joining.Consequently,several works pertaining to dissimilar joining,specifically Al?Cu,are available in the literature but they are scattered in different sources,which makes the task of gatheringinformation about dissimilar FSW of Al?Cu cumbersome.This work has been written with an aim to provide all pertinentinformation related to dissimilar FSW of Al?Cu at one place to ease the problems of researchers.It comprehensively covers andsummarizes the topics such as the effect of tool design and geometry,FSW process parameters,FSW strategies on mechanicalproperties,microstructure and formation of defects during dissimilar FSW of Al?Cu.In addition,it also presents and discussesseveral variants of dissimilar FSW of Al?Cu.Finally,this work not only puts forth major findings of the previous researchers but alsosuggests future recommendations for dissimilar FSW of Al?Cu.展开更多
文摘Sizes of nuggets are often used to evaluate spot weld quality in production. This paper presents a neural estimator used to carry out non-destructive on-line analysis of spot weld quality in which trained ANN functions to map dynamic resistance characteristics into sizes of spot weld nuggets and results confirm the validity of neural network for this type of application.
文摘Our study investigated the effect of utiliz</span></span><span><span><span style="font-family:;" "="">ing</span></span></span><span><span><span style="font-family:;" "=""> chicken</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">wings and dehydrated shellfish to produce chicken nuggets rich in protein, minerals and vitamins.</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">The proximate composition, nutritional value, physical and sensorial properties were evaluated. The different</span></span></span><span><span><span style="font-family:;" "="">ly</span></span></span><span><span><span style="font-family:;" "=""> prepared chicken nuggets </span></span></span><span><span><span style="font-family:;" "="">were </span></span></span><span><span><span style="font-family:;" "="">supplemented with dehydrated shellfish CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0%, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">2%, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">4% and CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6%. There was </span></span></span><span><span><span style="font-family:;" "="">a </span></span></span><span><span><span style="font-family:;" "="">significantly reduction </span></span></span><span><span><span style="font-family:;" "="">in </span></span></span><span><span><span style="font-family:;" "="">moisture and </span></span></span><span><span><span style="font-family:;" "="">an </span></span></span><span><span><span style="font-family:;" "="">increasing in protein content (<i>P</i> < 0.05) in all Chicken Nuggets (CN) in comparison to the control. Fat content was significantly higher in CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0% than CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">2%, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">4% and CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6%. Ash content was increasing with added dehydrated shellfish, while </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">reduction in carbohydrates and total calories of the different chicken nuggets were noticed with </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">significant gradual rise in pH values, TBA values showed no significant difference (<i>P</i> < 0.05) between chicken nuggets. Results showed that using dehydrated shellfish in preparing chicken nuggets caused a marked rise in its content of Ca, Fe, Na, K, Zn, Mg and Mn levels, CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0% had the lowest concentration of all minerals, and had lower value</span></span></span><span><span><span style="font-family:;" "="">s</span></span></span><span><span><span style="font-family:;" "=""> of vitamins A, E and D but CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6% had higher value</span></span></span><span><span><span style="font-family:;" "="">s</span></span></span><span><span><span style="font-family:;" "=""> of vitamins A, E and D. Control Nuggets (CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">0%) had the lowest value of yellowness and highest value of lightness but CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">6% had </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">highest value of yellowness and, </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">lowest value of lightness. </span></span></span><span><span><span style="font-family:;" "="">The </span></span></span><span><span><span style="font-family:;" "="">redness had </span></span></span><span><span><span style="font-family:;" "="">a </span></span></span><span><span><span style="font-family:;" "="">slightly reduction. All samples showed slight changes in</span></span></span><span><span><span style="font-family:;" "=""> hardness, cohesiveness, springiness, gumminess and chewiness were noticed. </span></span></span><span><span><span style="font-family:;" "="">An </span></span></span><span><span><span style="font-family:;" "="">increase in WHC, pick-up, and cooking loss of chicken nuggets with dehydrated shellfish was noticed. Panelists accepted all prepared chicken nuggets and the chicken nuggets CN</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">4% had </span></span></span><span><span><span style="font-family:;" "="">the </span></span></span><span><span><span style="font-family:;" "="">highest score compared with other chicken nuggets prepared.
基金supported by the National Natural Science Foundation of China (11203018)the West Light Foundation (XBBS-2014-23)+1 种基金the Science Project of Universities in Xinjiang (XJEDU2012S02)the Doctoral Science Foundation of Xinjiang University (BS120107)
文摘Pulsar glitches, i.e. the sudden spin-ups of pulsars, have been detected for most known pulsars.The mechanism giving rise to this kind of phenomenon is uncertain, although a large data set has been built.In the framework of the starquake model, based on Baym ＆ Pines, the glitch sizes（the relative increases of spin-frequencies during glitches） △Ω/Ω depend on the released energies during glitches, with less released energies corresponding to smaller glitch sizes. On the other hand, as one of the dark matter candidates,our Galaxy might be filled with so called strange nuggets（SNs） which are relics from the early Universe.In this case collisions between pulsars and SNs are inevitable, and these collisions would lead to glitches when enough elastic energy has been accumulated during the spin-down process. The SN-triggered glitches could release less energy, because the accumulated elastic energy would be less than that in the scenario of glitches without SNs. Therefore, if a pulsar is hit frequently by SNs, it would tend to have more small glitches, whose values of ？？/？ are smaller than those in the standard starquake model（with larger amounts of released energy）. Based on the assumption that in our Galaxy the distribution of SNs is similar to that of dark matter, as well as on the glitch data in the ATNF Pulsar Catalogue and Jodrell Bank glitch table, we find that in our Galaxy the incidences of small glitches exhibit tendencies consistent with the collision rates between pulsars and SNs. Further testing of this scenario is expected by detecting more small glitches（e.g.,by the Square Kilometre Array）.
基金Sponsored by National Science and Technology Support Plan of China(2012BAB14B00)
文摘In order to utilize the iron resource effectively in red mud, a laboratory experiment based on the orthogonal method was carried out. Nuggets were gotten by directly reducing the carbon-bearing pellets of red mud and coal. The results showed that the strongest influencing factor is temperature, and the separation between liquid iron and slag is thoroughly. The nuggets can be gotten when the pellets, in which xC/xO is 1.6 and the basicity is 1.0, were maintained in 30 min at 1 400 ℃. The nuggets have a high TFe content which is higher than that in the hot metal produced in BF. It also has a low content of Si and Mn, but a high content of S and P. The main compositions of the slag are amorphous phase mainly containing SiO;and unreduced Fe;SiO;. Of course, a little reduced iron retains in it.
基金the Coordinación de la Investigación Científica(CIC)of the Universidad Michoacana de San Nicolás de Hidalgo(UMSNH-México)for the support during this project(CIC-UMSNH-1.8)sponsored by the National Council on Science and Technology(Consejo Nacional de Ciencia y Tecnología-México)and would like to thank for the support during this project N.B.254928
文摘Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, C, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.
基金Supported in part by the National Natural Science Foundation of China (12235016, 12221005)the Strategic Priority Research Program of Chinese Academy of Sciences (XDB34030000)。
文摘Affleck-Dine baryogenesis generated high baryon density in the early Universe. The baryon chemical potential enhanced the potential barrier and significantly reduced the decay rate of false vacuum, which decreased from infinity at the critical end point to zero at the critical nucleation point. When the decay rate reached zero, the false vacuum of high baryon density quark matter was unlikely to decay and could persist over cosmological time scales. Therefore, primordial quark nuggets(PQNs) could form and survive in the early Universe as the seeds of compact stars. This new mechanism for the formation of PQNs is different from Witten's stable droplet of quark matter.
文摘Petrography and mineral chemistry of Ca, Al-rich inclusions of Ningqiang carbonaceous chondrite are studied and the highly Re-Os fractionated Pt-metal nuggets in it is discovered. The refractory inclusions are classified into melilite-spinel-rich, and spinel-pyroxene-rich types. The former probably crystallized from melts, while the latter could be aggregates of the nebular condensates. The strong f ractionation between Re and Os suggests a pre-solar origin of the Pt-metal nuggets, which probably experienced various processes of formation and evolution before being captured by the refractory inclusions as indicated by the depletions of W and Mo.
文摘This paper focuses on the effect of welding parameters on microstructure and tensile strength of joints welded by friction-stir welding(FSW).The effects of pin profile(threaded conical,non-threaded conical and triangular pin),tool rotational speed(800,1000,1250 and 1600 r·min^(-1))and welding speed(63,80,100 and 125 mm·min^(-1))on the mechanical and microstructural properties of joints welded in 5-mm 7075-T6 were investigated.The results depict that the pin profile has a major role in the shape and grain size of the weld nugget zone(WNZ).In other words,a wider weld nugget and a finer grain size by threaded conical pin are obtained in WNZ.The attained data of tensile tests show that the maximum ultimate tensile strength(UTS)belongs to the threaded conical pin which is attributed to a finer grain size generated in the weld nugget zone.Additionally,it is found that the tensile strength increases with the welding speed increasing,whereas rotational speed has a bilateral effect on the tensile strength.The microhardness tests show that the minimum hardness is obtained in the heat-affected zone(HAZ).
文摘Chicken nugget is a comminuted meat product commonly prepared from spiced chicken meat and other ingredients. The tenderness of chicken meat lowers its firmness and mouth feel which may reduce acceptability of chicken nugget made from it. Thus, acceptability of chicken nugget could be harnessed when legume flour extenders are used along. Therefore, acceptability as well as quality of chicken nugget from different legume flours were evaluated. Soyabean, groundnut and cowpea flours were used as meat extenders for development of raw chicken nuggets and thereafter cooked for consumption. The quality of both raw and cooked legume flour extended chicken nuggets were assessed based on functional properties, sensory properties, proximate composition, amino acid content and shelf stability in terms of lipid peroxidation and microbial load. In their raw state, the legume flour extenders competed favourably with each other. Among all, soyabean flour extender maintained remarkable functional properties that transcend into significant (P < 0.05) yield of 86.93% of chicken nugget in comparison to the control (86.37%), groundnut (84.95%) and cowpea (84.50%). Upon cooking, all the legume flour extended chicken nuggets varied in their quality attributes. Apart from the high level of flavour and low microbial load, cowpea extended chicken nugget was of low quality based on the parameters evaluated in comparison with other legume flour extended chicken nuggets. Of interest, soyabean extended chicken nugget followed by groundnut extended chicken nugget were of good quality based on sensory properties, high crude protein and amino acid levels, low cholesterol content and lipid peroxidation value as well as low microbial load.
文摘The objective of this study is preparation of new <b>nutritious</b> products from quail meat compared to other products prepared from chicken meat as control and commercial products which bought from supermarket. The proximate composition, chemical, physical and sensorial properties were evaluated. The different products were prepared as sausage form quail meat (SQ), chicken meat (SC) and commercial (SCo), and, kofta from quail meat (KQ), chicken meat (KC) and commercial (KCo), and, nuggets from quail meat (NQ), chicken meat (NC) and commercial (NCo). The result observed that the chemical composition of products that prepared from quail meat recorded the highest content of protein and ash, on contrary, the lowest content of fat compared with products that prepare from chicken meat as control or commercial. All products that prepared from quail meat recorded high content of K, Ca, Mg, P, Fe, Zn, Se and vitamin A, Kofta was </span></span><span><span><span style="font-family:"">the </span></span></span><span><span><span style="font-family:"">highest one followed by nuggets then sausage products. While sausage products that prepared from both quail and chicken meat as control recorded the highest content of vitamin E, followed nuggets and kofta, respectively compared with commercial products. The results indicated decreasing cooking loss after preparing of quail meat products followed by both chicken meat products as control and commercial product</span></span></span><span><span><span style="font-family:"">, </span></span></span><span><span><span style="font-family:"">increasing water capacity (WHC)</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:"">of KQ and plasticity of SQ and NQ. All products were accepted from panelists while slightly significant difference among these products (P > 0.05). SC was the highest score in colour, taste, odour, texture and overall acceptability compared with SQ and SCo. Generally products were prepared from quail meat </span></span></span><span><span><span style="font-family:"">which </span></span></span><span><span><span style="font-family:"">showed high acceptance in sensory evaluation by panelists.
文摘Components made by joining different materials are required in various engineering applications.Fabrication of suchcomponents is a challenging task due to the vast difference in mechanical,thermal and electrical properties of the materials beingused.Friction stir welding(FSW)is capable of joining dissimilar materials such as aluminum(Al)and copper(Cu)and thereforeresearchers have used this novel process for dissimilar joining.Consequently,several works pertaining to dissimilar joining,specifically Al?Cu,are available in the literature but they are scattered in different sources,which makes the task of gatheringinformation about dissimilar FSW of Al?Cu cumbersome.This work has been written with an aim to provide all pertinentinformation related to dissimilar FSW of Al?Cu at one place to ease the problems of researchers.It comprehensively covers andsummarizes the topics such as the effect of tool design and geometry,FSW process parameters,FSW strategies on mechanicalproperties,microstructure and formation of defects during dissimilar FSW of Al?Cu.In addition,it also presents and discussesseveral variants of dissimilar FSW of Al?Cu.Finally,this work not only puts forth major findings of the previous researchers but alsosuggests future recommendations for dissimilar FSW of Al?Cu.
