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基于小流域山坪塘沉积泥沙^(137)Cs的泥沙沉积剖面粒径特征

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节水灌溉 2025年第1期 96-101页

作者：成六三重庆工程职业技术学院重庆402260

小流域泥沙来源分析对流域综合治理与水土保持措施评价具有重要意义。选择岩溶区小流域山坪塘为例,从山坪塘沉积泥沙入手,探明山坪塘沉积泥沙剖面与其控制流域内的土地利用类型的^(137)Cs比活度和及黏粒含量的深度分布特征,为反演小流... 详细信息

小流域泥沙来源分析对流域综合治理与水土保持措施评价具有重要意义。选择岩溶区小流域山坪塘为例,从山坪塘沉积泥沙入手,探明山坪塘沉积泥沙剖面与其控制流域内的土地利用类型的^(137)Cs比活度和及黏粒含量的深度分布特征,为反演小流域土壤侵蚀时空强度分布提供基础。研究结果表明:①山坪塘沉积泥沙的^(137)Cs比活度在垂直剖面上变化较为复杂,最大值出现在山坪塘的底顶部,^(137)Cs比活度范围为0.99~3.58 Bq/kg,平均值为1.8 Bq/kg;②山坪塘控制流域内坡耕地、草地和林地表层土壤的^(137)Cs比活度分布差异性较大,且^(137)Cs比活度极差分别为4.16、2.86和6.36 Bq/kg;③山坪塘旋回沉积泥沙与其控制流域内土地利用类型表层土壤的粒径组分含量主要以黏粒、中粉粒和粉粒为主,且它们的粒径组分含量之间比例基本保持一致;④山坪塘沉积泥沙粒径特征参数(中值粒径、众数粒径、体积加权平均粒径和分形维数D)在垂直剖面上变化基本保持一致,而有效粒径变化较为复杂。研究为开展岩溶小流域山坪塘泥沙沉积来源特征演变提供了重要基础。

关键词：岩溶小流域 ^(137)Cs 土壤侵蚀乌江流域

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Ri.osome profi.i.g and si.gle-cell RNA sequenci.g i.enti.y the unfolded protei. response as a key regulator of pi.eon lactati.n

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Zoologi.al Research 2025年第01期 54-74页

作者： Ji.g Li. san-Feng Li. Hui.Rong Mao Hong-Xi. Ji.ng Shui.Bi.g Li. Xi.o-Fei.Xu Ji.-Tao Wu Xun Li. Wen-Tao Zhang Xi.o-Long Hu Bi.o Chen College of Ani.al Sci.nce and Technology Jiangxi Agricultural University Poultry i.sti.ute Jiangxi Agricultural University Zhongshan Shi.i.Pi.eon Breedi.g Li.i.ed Company Nati.nal Key Laboratory for Swi.e Geneti. i.provement and Germplasm i.novati.n Ministry of Science and Technology of ChinaJiangxi Agricultural University

Pi.eons and certai. other avi.n speci.s produce a mi.kli.e secreti.n i. thei. crop sacs to nouri.h offspri.g, yet the detai.ed processes i.volved are not fully eluci.ated. Thi. study i.vesti.ated the crop sacs of 225-day-old unpai.ed non-lactati.g male pi.eons(MN) and males i.i.i.ti.g lactati.n on the fi.st day after i.cubati.n(ML). Usi.g RNA sequenci.g,ri.osomeprofi.i.g,andsi.gle-cell transcri.tome sequenci.g(scRNA-seq), we i.enti.i.d a si.ni.i.ant up-regulati.n of genes associ.ted wi.h ri.osome assembly and protei. synthesi. i. ML compared to MN. Results from scRNA-seq analysi. i.enti.i.d 12di.ti.ct cell types and 22 clusters, wi.h secretory epi.heli.l cells(SECs) exhi.i.i.g marked expressi.n of plasma cell markers, i.cludi.g i.LL1 and MZB1. RNA fluorescence i. si.u hybri.i.ati.n(RNA Fi.H) and i.Y quanti.i.ati.n confi.med the cri.i.al role of SECs i. produci.g endogenous i.Y duri.g lactati.n. We propose that fi.roblast-deri.ed BAFF si.nals acti.ate SECs, mi.i.ki.g B cell transformati.n and enhanci.g protei. producti.n through the unfolded protei. response(UPR). These fi.di.gs shed li.ht on the cellular dynami.s of pi.eon mi.k producti.n and contri.ute to a broader understandi.g of avi.n bi.logy.

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工业复杂结构钣金模具冲压成形工艺优化研究

模具制造 2025年第2期25卷 7-9页

作者：桑晶南京机电职业技术学院江苏南京211306

为了优化复杂结构钣金模具的冲压成形工艺,提高成形精度与生产效率,通过对模具结构、材料变形机理以及工艺参数的系统分析,提出了优化方案,并通过实验验证了方案的有效性。结果表明,优化后的工艺能显著提升钣金件的成形质量,降低生产成... 详细信息

为了优化复杂结构钣金模具的冲压成形工艺,提高成形精度与生产效率,通过对模具结构、材料变形机理以及工艺参数的系统分析,提出了优化方案,并通过实验验证了方案的有效性。结果表明,优化后的工艺能显著提升钣金件的成形质量,降低生产成本,具有较高的工程应用价值。

关键词：钣金模具冲压成形工艺优化模具设计

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二维Janus LuCli.铁谷特性研究

原子与分子物理学报 2025年第2期42卷 159-168页

作者：朱靖欣郭三栋西安邮电大学电子工程学院西安710121

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了Janus单层LuCli.动力学、力学和热力... 详细信息

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了Janus单层LuCli.动力学、力学和热力学稳定性.发现Janus单层LuCli.一种有潜力的铁谷材料,它有着50.927 meV的谷劈裂.当Lu原子磁矩方向(平面外)发生颠倒时,可以实现谷极化翻转.还计算了Janus单层LuCli.布里渊区中的Berry曲率分布,主要集中在-K和K谷,可以实现反常谷霍尔效应.当电子关联强度比较小时,Janus单层LuCli.易磁化轴将指向面内,从而失去自发谷极化.尽管如此,利用应变调控可以使磁化方向从面内转向面外,从而产生谷极化.此外,Janus单层LuCli.时具有面内和面外压电响应,计算得到的面内压电应变系数d11大于大部分已有二维材料的计算值,而面外压电系数d31非常小.这为通过压电效应调控谷载流子提供了可能性.

关键词：铁谷材料压电第一性原理计算

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Apoli.oprotei. A-i.bi.di.g protei.-medi.ted neuroprotecti.n i. glaucomatous neuroi.flammati.n and neurodegenerati.n

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Neural Regenerati.n Research 2025年第5期20卷 1414-1415页

作者： Si.woo Hwang Seunghwan Choi.Soo-Ho Choi.Keun-Young Ki. Yury i.Mi.ler Won-Kyu Ju Hami.ton Glaucoma Center and Shi.ey Eye i.sti.ute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medi.i.e University of California San DiegoLa JollaCAUSA Nati.nal Center for Mi.roscopy and i.agi.g Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma i. a multi.actori.l eye di.order that can cause vi.i.n loss and i.reversi.le bli.dness,affecti.g i.di.i. uals aged 40 to 80 yea rs *** to the agi.g populati.n,i. i. expected that the number of people affected by glaucoma wi.l surpass 111 mi.li.n by 2040 as the di.ease becomes more *** pri.ari.y contri.utes to opti. nerve axon loss and the progressi.e degenerati.n of reti.al gangli.n cells (RGCs),subsequently leadi.g to vi.i.n i.pai.ment.

关键词： i.reversi.le pass pri.ari.y

Latti.e desi.n for a hybri. multi.bend achromat li.ht source

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Nuclear Sci.nce and Techni.ues 2020年第7期31卷 55-64页

作者： Eun-san Ki. Department of Accelerator Sci.nce Korea University Sejong CampusSejong 30019Korea

We present a latti.e desi.n and beam dynami.s analysi. for a 4 GeV low-emi.tance,hi.h-bri.li.nce synchrotron li.ht *** latti.e consi.ted of 26 si.-bend achromats wi.h 26 long and 26 short strai.ht *** present the desi.n results for a hybri. multi.bend achromat(HMBA)latti.e wi.h a natural emi.tance of 168 pm and ci.cumference of 729.3 *** cell had 4 longi.udi.al gradi.nt bendi.gs,2 combi.ed bendi.gs,14 quadrupoles,and 2 fami.i.s of *** latti.e was desi.ned to beflexi.le to provi.e both nonzero and zero di.persi.n functi.ns i. the long strai.ht *** two strai.ht secti.ns i. each cell had lengths of 5.6 and 1.2 *** ensure suffi.i.nt i.jecti.n,we opti.i.ed the desi.n latti.e and dynami. *** i.vesti.ated the dynami. aperture i. the latti.e wi.h machi.e errors,and the results showed that the latti.e desi.n provi.es suffi.i.nt dynami. aperture after COD correcti.n for beam *** present the results of an i.jecti.n scheme that demonstrates the space i. the i.jecti.n secti.n and the parti.le moti.ns of the i.jected *** also present the results of beam tracki.g after the beam i.jecti.n to exami.e the characteri.ti.s of the beam *** desi.ned HMBA latti.e was well opti.i.ed i. terms of the beam parameters and bri.li.nce as an i.termedi.te li.ht source at 4 GeV and a ci.cumference of 729.3 m.

关键词： i.jecti.n beam latti.e

i.proved adapti.e pruni.g algori.hm for least squares support vector regressi.n

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Journal of Systems Engi.eeri.g and Electroni.s 2012年第3期23卷 438-444页

作者： Runpeng Gao Ye san Control and Si.ulati.n Center Harbin Institute of TechnologyHarbin 150001P.R.China

As the soluti.ns of the least squares support vector regressi.n machi.e （LS-SVRM） are not sparse, i. leads to slow predi.ti.n speed and li.i.s i.s appli.ati.ns. The defects of the ex- i.ti.g adapti.e pruni.g algori.hm for LS-SVRM are that the trai.i.g speed i. slow, and the generali.ati.n performance i. not sati.- factory, especi.lly for large scale problems. Hence an i.proved algori.hm i. proposed. i. order to accelerate the trai.i.g speed, the pruned data poi.t and fast leave-one-out error are employed to vali.ate the temporary model obtai.ed after decremental learni.g. The novel objecti.e functi.n i. the termi.ati.n condi.i.n whi.h i.- volves the whole constrai.ts generated by all trai.i.g data poi.ts and three pruni.g strategi.s are employed to i.prove the generali. zati.n performance. The effecti.eness of the proposed algori.hm i. tested on si. benchmark datasets. The sparse LS-SVRM model has a faster trai.i.g speed and better generali.ati.n performance.

关键词： least squares support vector regressi.n machi.e (LS- SVRM) pruni.g leave-one-out (LOO) error i.cremental learni.g decremental learni.g.

RBF neural network based on q-Gaussi.n functi.n i. functi.n approxi.ati.n

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Fronti.rs of Computer Sci.nce 2011年第4期5卷 381-386页

作者： Wei.ZHAO Ye san Control and Si.ulati.n Center Harbin Institute of Technology Harbin 150001 China

To enhance the generali.ati.n performance of radi.l basi. functi.n （RBF） neural networks, an RBF neural network based on a q-Gaussi.n functi.n i. proposed. A q-Gaussi.n functi.n i. chosen as the radi.l basi. functi.n of the RBF neural network, and a parti.le swarm opti.i.ati.n algori.hm i. employed to select the parameters of the network. The non-extensi.e entropi. i.dex q i. encoded i. the parti.le and adjusted adapti.ely i. the evoluti.nary process of populati.n. Si.ulati.n results of the functi.n approxi.ati.n i.di.ate that an RBF neural network based on q-Gaussi.n functi.n achi.ves the best generali.ati.n performance.

关键词： radi.l basi. functi.n (RBF) neural network,q-Gaussi.n functi.n parti.le swarm opti.i.ati.n algo-ri.hm functi.n approxi.ati.n

Gender, i.tra-Household Dynami.s, and Household Hurri.ane Preparedness: An Exploratory Study Employi.g a Dyadi. i.tervi.w Approach

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i.ternati.nal Journal of Di.aster Ri.k Sci.nce 2018年第1期9卷 16-27页

作者： Li.san Hung Department of Geography Pennsylvania State University

Thi. exploratory study targets marri.d, heterosexual couples li.i.g i. Sarasota County, Flori.a and uses a dyadi. i.tervi.w approach to understand how the i.teracti.ns of marri.d couples, or i.tra-household dynami.s,could affect household hurri.ane preparedness. i.tervi.w results reveal that couples consi.er household hurri.ane preparedness to be a joi.t process between husband and wi.e, but i. many cases, partners do not have the same opi.i.ns about these preparati.ns. Thi. study also shows the relati.ns between household hurri.ane preparedness and household di.i.i.n of labor, and how the tendency of wi.es to pri.ri.i.e relati.nal preparedness acti.i.i.s could be an answer to understandi.g why some quanti.ati.e studi.s show that females have lower preparedness levels than males. Other potenti.l problems wi.h thi. previ.us research, i.cludi.g the selecti.n of survey parti.i.ants and the measurement of household hurri.ane preparedness, are li.ewi.e di.cussed.

关键词： Dyadi. i.tervi.ws Gender Household deci.i.n maki.g Household hurri.ane preparedness i.tra-household dynami.s