欧洲核子研究中心实验首次观测到物质-反物质不对称现象|AV免费网站在线观看
1. av免费网站在线观看人数在哪
2. av免费网站在线观看地址
3. av免费网站在线观看新
4. av免费网站在线观看新品
中新网北京7月18日电 (记者 孙自法)国际学术期刊《自然》最新发表一篇粒子物理学论文称,在欧洲核子研究中心(CERN)大型强子对撞机(LHC)上的LHCb实验中,科学家们首次观测到难以捉摸的、一种重子类的衰变复合亚原子粒子中存在物质-反物质不对称现象。
该论文介绍,这一效应被称为电荷-宇称联合(CP)对称性破坏,此前已有理论预测,但在重子中从未被观察到。这一实验验证尤为重要,因为重子构成了可观测宇宙中的大部分物质。
宇宙学模型认为,物质和反物质在大爆炸中等量产生,但在今日的宇宙中,物质似乎占据主导地位。这种不平衡被认为是由于物质和反物质行为差异造成的:一种被称为CP破坏的对称性破坏。
这一效应被物理学标准模型预测,60多年前已在称为介子的亚原子粒子中观测到,但在重子中尚未观察到。和两个夸克组成的介子不同,重子有3个夸克,构成大多数物质的粒子如中子和质子,都是重子。
在本项研究中,大型强子对撞机LHCb实验合作组利用LHC质子-质子碰撞的数据,提出对重子衰变中CP破坏的首次观察,发现CP不对称揭示出重子物质和反物质之间的行为差异。尽管这种破坏已得到预测,也不会解决大爆炸物质-反物质不平衡问题,但揭示其细节带来了重要线索,为进一步对CP破坏性质进行理论和实验研究开辟了路径。
LHCb实验合作组总结说,最新发表的这些研究发现,可能为探索标准模型之外的物理学铺平道路。(完)
zhongzhiyachishiyizhonggexindeyakezhiliaofangan,zhizaibangzhunaxieyingezhongyuanyinshiquyachiderenhuifukouqianggongnenghemeiguan。zhexiangjishuzi20shiji60niandaiyilaibuduanfazhan,yijingchengweiyakexiufulingyudezhongyaoxuanze。zhongzhiyadejibenyuanlishijiangyizhongchengwei“zhongzhiti”detaijinshuxiaozhusurgicallyzhirudaoyacaoguzhong,moniziranyagendegongneng。jingguoyiduanshijian,zhongzhitihuiyugugefashengjiehe,xingchengwengudejichu。suihou,yayihuizaizhongzhitishanganzhuangrenzaoyaguan,yishixianmeiguanhejujiaogongnengdehuifu。zhongzhiyadeyoushibushengmeiju。shouxian,zhongzhiyakeyiyouxiaodihuifujujiaogongneng,shihuanzhenenggoushunchangdijinshigezhongshiwu,gaishanleshenghuozhiliang。yuchuantongdejiayabutong,zhongzhiyabuyilaiyulinjindeyachi,yincibuhuiduiqitajiankangdeyachizaochengsunhai。qici,zhongzhiyajuyoujiaoqiangdewendingxinghenaiyongxing,changchangnenggoushiyong10nianhuogengchangshijian,wuxupinfangenghuan。ciwai,zhongzhiyazaiwaiguanshanggengjiejinziranyachi,nenggouhuifuhuanzhezixindeweixiao。raner,zhongzhiyabingfeishihesuoyouren。zaijinxingzhongzhiyashoushuzhiqian,yayihuipingguhuanzhedezhengtijiankangzhuangkuang、kouqiangtiaojianheguliang。ruguohuanzhedeguliangbuzu,kenengxuyaojinxingguyizhidengewaizhiliao。ciwai,huanzhexubaochilianghaodekouqiangweisheng,yiquebaozhongzhitidechenggonghechangqiwending。zhidezhuyideshi,suiranzhongzhiyadechenggonglvjiaogao,danshoushurengrancunzaiyidingdefengxian,kenengchuxianganran、shenjingsunshanghuozhongzhishibaidengqingkuang。yinci,zaixuanzezhongzhiya种(zhong)植(zhi)牙(ya)齿(chi)是(shi)一(yi)种(zhong)革(ge)新(xin)的(de)牙(ya)科(ke)治(zhi)疗(liao)方(fang)案(an),(,)旨(zhi)在(zai)帮(bang)助(zhu)那(na)些(xie)因(yin)各(ge)种(zhong)原(yuan)因(yin)失(shi)去(qu)牙(ya)齿(chi)的(de)人(ren)恢(hui)复(fu)口(kou)腔(qiang)功(gong)能(neng)和(he)美(mei)观(guan)。(。)这(zhe)项(xiang)技(ji)术(shu)自(zi)2(2)0世(shi)纪(ji)6(6)0年(nian)代(dai)以(yi)来(lai)不(bu)断(duan)发(fa)展(zhan),(,)已(yi)经(jing)成(cheng)为(wei)牙(ya)科(ke)修(xiu)复(fu)领(ling)域(yu)的(de)重(zhong)要(yao)选(xuan)择(ze)。(。)种(zhong)植(zhi)牙(ya)的(de)基(ji)本(ben)原(yuan)理(li)是(shi)将(jiang)一(yi)种(zhong)称(cheng)为(wei)“(“)种(zhong)植(zhi)体(ti)”(”)的(de)钛(tai)金(jin)属(shu)小(xiao)柱(zhu)s(s)u(u)r(r)g(g)i(i)c(c)a(a)l(l)l(l)y(y)植(zhi)入(ru)到(dao)牙(ya)槽(cao)骨(gu)中(zhong),(,)模(mo)拟(ni)自(zi)然(ran)牙(ya)根(gen)的(de)功(gong)能(neng)。(。)经(jing)过(guo)一(yi)段(duan)时(shi)间(jian),(,)种(zhong)植(zhi)体(ti)会(hui)与(yu)骨(gu)骼(ge)发(fa)生(sheng)结(jie)合(he),(,)形(xing)成(cheng)稳(wen)固(gu)的(de)基(ji)础(chu)。(。)随(sui)后(hou),(,)牙(ya)医(yi)会(hui)在(zai)种(zhong)植(zhi)体(ti)上(shang)安(an)装(zhuang)人(ren)造(zao)牙(ya)冠(guan),(,)以(yi)实(shi)现(xian)美(mei)观(guan)和(he)咀(ju)嚼(jiao)功(gong)能(neng)的(de)恢(hui)复(fu)。(。)种(zhong)植(zhi)牙(ya)的(de)优(you)势(shi)不(bu)胜(sheng)枚(mei)举(ju)。(。)首(shou)先(xian),(,)种(zhong)植(zhi)牙(ya)可(ke)以(yi)有(you)效(xiao)地(di)恢(hui)复(fu)咀(ju)嚼(jiao)功(gong)能(neng),(,)使(shi)患(huan)者(zhe)能(neng)够(gou)顺(shun)畅(chang)地(di)进(jin)食(shi)各(ge)种(zhong)食(shi)物(wu),(,)改(gai)善(shan)了(le)生(sheng)活(huo)质(zhi)量(liang)。(。)与(yu)传(chuan)统(tong)的(de)假(jia)牙(ya)不(bu)同(tong),(,)种(zhong)植(zhi)牙(ya)不(bu)依(yi)赖(lai)于(yu)邻(lin)近(jin)的(de)牙(ya)齿(chi),(,)因(yin)此(ci)不(bu)会(hui)对(dui)其(qi)他(ta)健(jian)康(kang)的(de)牙(ya)齿(chi)造(zao)成(cheng)损(sun)害(hai)。(。)其(qi)次(ci),(,)种(zhong)植(zhi)牙(ya)具(ju)有(you)较(jiao)强(qiang)的(de)稳(wen)定(ding)性(xing)和(he)耐(nai)用(yong)性(xing),(,)常(chang)常(chang)能(neng)够(gou)使(shi)用(yong)1(1)0年(nian)或(huo)更(geng)长(chang)时(shi)间(jian),(,)无(wu)需(xu)频(pin)繁(fan)更(geng)换(huan)。(。)此(ci)外(wai),(,)种(zhong)植(zhi)牙(ya)在(zai)外(wai)观(guan)上(shang)更(geng)接(jie)近(jin)自(zi)然(ran)牙(ya)齿(chi),(,)能(neng)够(gou)恢(hui)复(fu)患(huan)者(zhe)自(zi)信(xin)的(de)微(wei)笑(xiao)。(。)然(ran)而(er),(,)种(zhong)植(zhi)牙(ya)并(bing)非(fei)适(shi)合(he)所(suo)有(you)人(ren)。(。)在(zai)进(jin)行(xing)种(zhong)植(zhi)牙(ya)手(shou)术(shu)之(zhi)前(qian),(,)牙(ya)医(yi)会(hui)评(ping)估(gu)患(huan)者(zhe)的(de)整(zheng)体(ti)健(jian)康(kang)状(zhuang)况(kuang)、(、)口(kou)腔(qiang)条(tiao)件(jian)和(he)骨(gu)量(liang)。(。)如(ru)果(guo)患(huan)者(zhe)的(de)骨(gu)量(liang)不(bu)足(zu),(,)可(ke)能(neng)需(xu)要(yao)进(jin)行(xing)骨(gu)移(yi)植(zhi)等(deng)额(e)外(wai)治(zhi)疗(liao)。(。)此(ci)外(wai),(,)患(huan)者(zhe)须(xu)保(bao)持(chi)良(liang)好(hao)的(de)口(kou)腔(qiang)卫(wei)生(sheng),(,)以(yi)确(que)保(bao)种(zhong)植(zhi)体(ti)的(de)成(cheng)功(gong)和(he)长(chang)期(qi)稳(wen)定(ding)。(。)值(zhi)得(de)注(zhu)意(yi)的(de)是(shi),(,)虽(sui)然(ran)种(zhong)植(zhi)牙(ya)的(de)成(cheng)功(gong)率(lv)较(jiao)高(gao),(,)但(dan)手(shou)术(shu)仍(reng)然(ran)存(cun)在(zai)一(yi)定(ding)的(de)风(feng)险(xian),(,)可(ke)能(neng)出(chu)现(xian)感(gan)染(ran)、(、)神(shen)经(jing)损(sun)伤(shang)或(huo)种(zhong)植(zhi)失(shi)败(bai)等(deng)情(qing)况(kuang)。(。)因(yin)此(ci),(,)在(zai)选(xuan)择(ze)种(zhong)植(zhi)牙(ya)