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<梅州>志遠輻射防護工程有限公司

梅(mei)(mei)州(zhou)醫用(yong)(yong)氣(qi)(qi)密(mi)門價(jia)格多少錢-廠家直銷-質(zhi)優價(jia)廉-梅(mei)(mei)州(zhou)氣(qi)(qi)密(mi)鉛(qian)(qian)(qian)門價(jia)格-梅(mei)(mei)州(zhou)生產廠家-批發零(ling)售-鉛(qian)(qian)(qian)是軟的(de)(de)(de)(de)(de)(de)重金(jin)屬(shu)(shu)，呈灰藍色(se)，新(xin)鮮斷面具有強烈的(de)(de)(de)(de)(de)(de)金(jin)屬(shu)(shu)光澤。鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)熔點(dian)低(327.4℃)、密(mi)度(du)(du)(du)大(11.68g/cm3)、流動性(xing)好(340℃時(shi)，其黏度(du)(du)(du)為0.019:、470℃時(shi)為0.014P)鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)沸(fei)點(dian)根據(ju)不(bu)(bu)(bu)同文獻資(zi)料，測得(de)(de)的(de)(de)(de)(de)(de)(de)數值均不(bu)(bu)(bu)一樣，不(bu)(bu)(bu)過(guo)現在大多數認為鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)沸(fei)點(dian)為1525℃。鉛(qian)(qian)(qian)在500-50℃時(shi)，便有顯著揮發，并具有毒性(xing)，所以(yi)生產過(guo)程中，應(ying)嚴格控(kong)制生產溫(wen)度(du)(du)(du)，盡量(liang)減少鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)揮發。鉛(qian)(qian)(qian)是熱(re)(re)和(he)電的(de)(de)(de)(de)(de)(de)不(bu)(bu)(bu)良導(dao)(dao)(dao)體，如果把銀的(de)(de)(de)(de)(de)(de)導(dao)(dao)(dao)熱(re)(re)度(du)(du)(du)和(he)導(dao)(dao)(dao)電度(du)(du)(du)當作則鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)導(dao)(dao)(dao)熱(re)(re)度(du)(du)(du)和(he)導(dao)(dao)(dao)電度(du)(du)(du)分別為銀的(de)(de)(de)(de)(de)(de)8.5％和(he)10.7％。鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)展性(xing)好，可(ke)以(yi)壓軋(ya)成(cheng)鉛(qian)(qian)(qian)皮或(huo)錘成(cheng)鉛(qian)(qian)(qian)箱，但(dan)(dan)是其延性(xing)差，不(bu)(bu)(bu)能(neng)(neng)拉成(cheng)鉛(qian)(qian)(qian)絲。常溫(wen)時(shi)，鉛(qian)(qian)(qian)在完全干(gan)燥(zao)的(de)(de)(de)(de)(de)(de)空氣(qi)(qi)中，不(bu)(bu)(bu)會發生任何化(hua)(hua)(hua)(hua)學反(fan)應(ying)；在潮濕(shi)和(he)含有二(er)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)碳(tan)的(de)(de)(de)(de)(de)(de)空氣(qi)(qi)中時(shi)，鉛(qian)(qian)(qian)會被(bei)(bei)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)而(er)(er)失(shi)去金(jin)屬(shu)(shu)光澤，其表(biao)面被(bei)(bei)二(er)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)鉛(qian)(qian)(qian)覆蓋而(er)(er)變(bian)成(cheng)暗(an)灰色(se)，此薄膜慢(man)(man)慢(man)(man)轉化(hua)(hua)(hua)(hua)，變(bian)成(cheng)堿性(xing)碳(tan)酸(suan)鉛(qian)(qian)(qian)，可(ke)防止內部繼續被(bei)(bei)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)；鉛(qian)(qian)(qian)在空氣(qi)(qi)中加(jia)熱(re)(re)熔化(hua)(hua)(hua)(hua)，開(kai)始氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)生產氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)鉛(qian)(qian)(qian)，繼續加(jia)熱(re)(re)到(dao)330450℃則氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)鉛(qian)(qian)(qian)轉化(hua)(hua)(hua)(hua)成(cheng)三(san)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)鉛(qian)(qian)(qian)，溫(wen)度(du)(du)(du)上升到(dao)450~470℃時(shi)，又轉化(hua)(hua)(hua)(hua)成(cheng)四(si)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)三(san)鉛(qian)(qian)(qian)，無(wu)論是三(san)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)二(er)鉛(qian)(qian)(qian)還是四(si)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)三(san)鉛(qian)(qian)(qian)，在高(gao)溫(wen)下都不(bu)(bu)(bu)穩定，易離解為氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)鉛(qian)(qian)(qian)和(he)氧(yang)(yang)(yang)(yang)(yang)。鉛(qian)(qian)(qian)易溶于硝酸(suan)，特別是稀(xi)硝酸(suan)、硼氟酸(suan)、硅氟酸(suan)和(he)醋(cu)酸(suan)；常溫(wen)下硫酸(suan)和(he)鹽酸(suan)僅作用(yong)(yong)于鉛(qian)(qian)(qian)表(biao)面，形成(cheng)幾(ji)乎不(bu)(bu)(bu)溶的(de)(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)(yang)化(hua)(hua)(hua)(hua)鉛(qian)(qian)(qian)和(he)硫酸(suan)鉛(qian)(qian)(qian)膜，保護表(biao)面，內層不(bu)(bu)(bu)再受(shou)酸(suan)的(de)(de)(de)(de)(de)(de)侵(qin)蝕，但(dan)(dan)在煮熱(re)(re)的(de)(de)(de)(de)(de)(de)鹽酸(suan)和(he)加(jia)熱(re)(re)至200℃的(de)(de)(de)(de)(de)(de)濃硫酸(suan)作用(yong)(yong)下，鉛(qian)(qian)(qian)能(neng)(neng)被(bei)(bei)慢(man)(man)慢(man)(man)地(di)溶解。雜(za)質(zhi)對鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)性(xing)質(zhi)有很大的(de)(de)(de)(de)(de)(de)影響(xiang)，鉛(qian)(qian)(qian)中含有少量(liang)的(de)(de)(de)(de)(de)(de)雜(za)質(zhi)，在如砷、銻、銅、 錫、堿金(jin)屬(shu)(shu)和(he)堿土金(jin)屬(shu)(shu)存在時(shi)不(bu)(bu)(bu)但(dan)(dan)會使(shi)(shi)得(de)(de)鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)硬度(du)(du)(du)增加(jia)、抗腐蝕性(xing)能(neng)(neng)降低，而(er)(er)且還會使(shi)(shi)得(de)(de)制成(cheng)的(de)(de)(de)(de)(de)(de)材料顏色(se)變(bian)壞，甚(shen)至根本不(bu)(bu)(bu)能(neng)(neng)使(shi)(shi)用(yong)(yong)。砷和(he)銻會使(shi)(shi)得(de)(de)鉛(qian)(qian)(qian)變(bian)得(de)(de)脆(cui)和(he)硬，鎘、碲和(he)錫能(neng)(neng)增大鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)硬度(du)(du)(du)和(he)疲勞極限，銅可(ke)以(yi)提高(gao)鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)熔點(dian)，鉍和(he)鋅(xin)均能(neng)(neng)增加(jia)鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)硬度(du)(du)(du)和(he)降低鉛(qian)(qian)(qian)的(de)(de)(de)(de)(de)(de)耐酸(suan)性(xing)能(neng)(neng)。