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1.
The induced matching partition number of graph G is the minimum integer k such that there exists a k-partition(V1,V2,…,Vk) of V(G)such that,for each i(1≤i≤k),G[Vi] is 1-regular.In this paper,we study the induced matching partition number of product graphs.We provide a lower bound and an upper bound for the induced matching partition number of product graphs,and exact results are given for some special product graphs. 相似文献
2.
The induced matching partition number of graph G is the minimum integer k such that there exists a k-partition （V1, V2,…,Vk） of V（G） such that, for each i（1≤i≤k）, G[V1] is 1-regular. In this paper, we study the induced matching partition number of product graphs. We provide a lower bound and an upper bound for the induced matching partition number of product graphs, and exact results are given for some special product graphs. 相似文献
3.
《中国科学院院刊(英文版)》2006,20(2)
People are always fascinated by ways that some members of mammalian species (such as dolphins, bats and some rodents) communicate using sounds that we cannot hear. But think twice if you say the capacity of producing and detecting ultrasounds (frequencies greater than 20kHz) is limited to mammalians. A study implemented by Prof. SHEN Junxian from the CAS Institute of Biophysics (IBP) and colleagues in CAS and abroad showed that a rare frog species in China should also be added to that list. It is the first documented case of a non-mammalian species being able to use ultrasonic communication. Their work was reported in the March 16 issue of the journal Nature. 相似文献
4.
Fang Xin 《中国科学院院刊(英文版)》2003,17(3)
Reform is a process of insti-tutional changes, in which,at any stage, the character-istics of a given institutional arrange-ment must have its contextual logicand cognate inter-relations of mu-tual causality. Just as Douglass C.North points out: History is alwaysimportant and its importance lies notonly in the fact that we might takesomething valuable from the past,but that the present and future areto link the past via the continuity ofa societys institutional system. Thechoice of today and … 相似文献
5.
《国家科学评论(英文版)》2014,(3)
The ecological water diversion project in the Heihe River Basin is the irst successful case in China in which the ecological systems in a river basin have been rescued. his project serves as a valuable example for the management of ecosystems in other inland river basins. his paper reviews the integrated studies of the water–ecosystem–economy relationship in the Heihe River Basin and concludes that sustainable development in inland river basins requires the basin to be considered as a whole, with the relationships between the upstream, midstream and downstream areas of the basin coordinated appropriately. Successful development in these basins will be relected in an improved output per cubic meter of water and the implementation of integrated river basin management practices. 相似文献
6.
《中国专利与商标》2006,(1)
The significance of the adjudication of the present case is whether the likelihood of confusion on the part of the relevant section of the public should be taken as the standard for deciding on infringement of the exclusive right to use a trademark. Where a registered trademark contains a set technical term of the national standards, the proprietor of the exclusive right to use the registered trademark has no right to prohibit others from normal use when exercising the said right. 相似文献
7.
Tian Junliang 《中国科学院院刊(英文版)》2003,17(2):101-106
Vegetation could be recovered in enclosed districts where soil erosion is controlled by integrated measures such as turning hillsides into terraces.The fragile eco-environment inthe west of China has be-come a bottleneck in theregions development. When puttingthe national strategy of developingthe western region into practice, thecentral authorities list the rehabilita-tion of the depleted eco-environmentas one of the key infrastructure pro-grams for the whole country, urgingpeople to return f… 相似文献
8.
《中国科学院院刊(英文版)》2005,(2)
With 230 speci esthroughout tropicaland subtr opicalAsia, Alpinia is the largest, mostwidespread and most taxonomicallycomplex genus in the ginger family(Zingiberaceae). Species of Alpiniaoften predominate in the understoryof forests, and some of them are im-p or t a nt o r n a m e nt al s an dmedicinals. By using DNA-se-quence-based methods, Prof. LiQ i n g j u n f r o m t h e C A SXishuangbanna Tropical BotanicalGarden and his collaborators fromthe US National Museum of Natu-ral His… 相似文献
9.
A karyotypical analysis of Anemarrhena asphodeloides Bung. of the monotypic genus
Anemarrhena Bung. (Liliaceae) was carried out for the first time. The number of chromo-
somes in root-tip cell of the species was found to be 22, agreeing with that reported by Sato[12], although inconsistent in some other respects, such as position of centromeres, length of chromosomes, and nucleoli, etc. (Table 1 ). According to the terminology defined by Levan et al.［8］, the karyotype formula is therefore 2n=22=2sm (SAT)+2sm+18m.
Photomicrographs of the chromosome complements and idiogram of the karyotype are given
Fig. 1 and 2).
The karyotype of Anemarrhena asphodeloides shows explicitly to be asymmetrical, with three pairs of long chromosomes and eight pairs of short chromosomes. This specialized feature, when considered together with the rare occurrence of the basic chromosome number of 11 of the genus within the Tribe Asphodeleae of Liliaceae (see Table 1), suggests that the genus Anemarrhena is probably a rather specialized one, which has scarcely any intimate relationship with the other genera of the above tribe. The fact that this specialized karyotype is associated with certain trends of morphological specialization, such as flowers possessing three stamens only, gives support to the above suggestion. But, it is impossible to draw a more precise conclusion without a more thorough and comprehensive investigation of the species in question. 相似文献
10.
《国家科学评论(英文版)》2015,(4)
The impact of the Tibetan Plateau uplit on the Asian monsoons and inland arid climates is an important but also controversial question in studies of paleoenvironmental change during the Cenozoic. In order to achieve a good understanding of the background for the formation of the Asian monsoons and arid environments, it is necessary to know the characteristics of the distribution of monsoon regions and arid zones in Asia before the plateau uplit. In this study, we discuss in detail the paterns of distribution of the Asian monsoon and arid regions before the plateau uplit on the basis of modeling results without topography from a global coupled atmosphere–ocean general circulation model, compare our results with previous simulation studies and available biogeological data, and review the uncertainties in the current knowledge. Based on what we know at the moment, tropical monsoon climates existed south of 20?N in South and Southeast Asia before the plateau uplit, while the East Asian monsoon was entirely absent in the extratropics. hese tropical monsoons mainly resulted from the seasonal shits of the Inter-Tropical Convergence Zone. here may have been a quasi-monsoon region in central-southern Siberia. Most of the arid regions in the Asian continent were limited to the latitudes of 20–40?N, corresponding to the range of the subtropical high pressure year-around. In the meantime, the present-day arid regions located in the relatively high latitudes in Central Asia were most likely absent before the plateau uplit. he main results from the above modeling analyses are qualitatively consistent with the available biogeological data. hese results highlight the importance of the uplit of the Tibetan Plateau in the Cenozoic evolution of the Asian climate patern of dry–wet conditions. Future studies should be focused on efects of the changes in land–sea distribution and atmospheric CO2 concentrations before and ater the plateau uplit, and also on cross-comparisons between numerical simulations and geological evidence, so that a comprehensive understanding of the evolution of the Cenozoic paleoenvironments in Asia can be achieved. 相似文献
11.
洪德元 《中国科学院研究生院学报》1980,18(1):50-52
While we were investigating the world Veroniceae we found the genus Wulfenia Jacq.
discontinuously distributing. W. carinthiaca and W. baldaccii are found in south-eastern Europe
and W. orientalis in Turkey and Lebanon, whereas W. amherstiana is a native of W. Hima-
laya. Such a pattern of distribution, discontinuous between the Mediterranean and W. Himala-
ya, as far as we know, is hardly frequent. After comparing carefully the specimens from these
two places and examining their pollen grains we got the impression that the difference between
the plants occuring near the Mediterranean and those in Himalaya is so big that they should
no longer be placed in the same genus. It would be necessary, therefore, to describe W. amhe-
rstiana as a new and separate genus (we name it Wulfeniopsis Hong). Its corolla is not 2-
lipped, but with four lobes (not five) lanceolate, acuminate and erect (not spreading). The
stigma is very small, not 2-lobed. Pollen grains are much smaller, with colpi more narrow and
lacking of membranes, and their exines are smooth (not reticulate). It’s chromosome numberis 2n = 16 (not 18). 相似文献
12.
《中国科学院院刊(英文版)》2006,20(2):90-91
Opaque assemblages (OAs) were once thought to be “the oldest objects in the solar system.” After careful studies of OAs in primitive meteorites, a group of Chinese and US scientists have recently found that this is not the case. The scientists speculate… 相似文献
13.
This paper deals with the taxa of tribe Arundinarieae Steud. subtribe Pleiobalastinae Keng and Keng f. which comprised three genera (Pseudosasa Makino, Pleioblastus Nakai and Brachystachyum Keng) when it was established in 1957. With the analysis of morphological characters and geographical distribution, a number of revisions connected with the taxon are made as follows:
(1) Genus Brachystachyum Keng is transferred to the tribe Shibataeeae Nakai ac-
cording to its false inflorescence.
(2) Genus Pseudosasa Makino is transferred to subtribe Sasinae Keng f. according to our study on the numerical taxonomic method.
(3) Some species of Pleioblastus Nakai established by Keng and Keng f. should be
revised. Pleioblastus actinotrichus (Merr. and Chun) Keng f. should be Ampelocalamus actinotrichus (Merr. and Chun) S. L. Chen, T. H. Wen and G. Y. Sheng in subtribe Tham-
nocalaminae Keng f.; Pleioblastus dolichanthus (Keng) Keng f. is the synonym of Sinobam-
busa tootsik (Sieb.) Makino, belonging to tribe Shibataeeae Nakai. The rest species remain in this genus. Since the genus Pleioblastus is related to genus Arundinaria Michaux., subtribe Pleioblastus Keng and Keng f. does not seem to have a reason to be retained as a subtribe in tribe Arundinarieae Steud., according to the newest Code (1978). A part of it should be a synonym of subtribe Arundinariinae and we may cite it as follows: Subtribe Arundinariinae——Subtribe Pleioblastinae Keng and Keng f. pro parte, syn. nov. The other parts of it should be transferred to other subtribes or tribes.
In addition, one new variety in Branchystachyum, two new species, one new variety in Pseudosasa and six new species, three new varieties in Pleioblastus, are described in this paper. 相似文献
14.
It is particularly important and necessary to try to make inlensive course interesting and effective for the students. Their study will become a lot more effective if the sludents eome to the classroom willingly instead of being forced to. That is 1o say, how a leacher can succeed in arousing the students＇ interest in intensive coarse mid making the students more active and aggressive in thinking, listening and speaking. For this purpose, we should change the leacher dominaled class for a student-centered one. 相似文献
15.
《中国科学院院刊(英文版)》2004,18(1):6-6
Flexibility of polyelectrolyte nanotubes is necessary if they are to be exploited in applications such as developing photoelectric devices with strong mechanical properties. In a recent attempt, high flexibility has been observed from such nanotubes prepared by a research team headed by Prof. Li Junbai of the CAS Institute of Chemistry (ICCAS). 相似文献
16.
《中国科学院院刊(英文版)》2019,(4)
The widespread application of new technologies, while empowering women with new opportunities, might also put them at disadvantage. For example, in comparison with males, the application of AI might be more likely to cost them their jobs. Meanwhile, women are missing out the opportunity to participate in the policy-making process – they are absent from the table. If no change is made in the current policies, we will miss the goal to achieve gender equality, the fifth of the 17 Sustainable Development Goals set for UN's 2030 Agenda for Sustainable Development, warned elite women scientists with the Organization for Women in Science for the Developing World(OWSD). What shall be done now? How can we make a difference? They are in action to help. 相似文献
17.
＂Of the Boy and Butterfly＂ by John Bunyan tells that a boy, greatly attracted by the beautiful colors of a butterfly, got rid of any difficulties he met to catch it, but when finally he got it, he didn＇t get the pleasure he expected, but felt lost as soon as won. Like the beardless boy, our adults always run after some empty toys, even at all hazards, but when we get them, we find they are but painted nothings and false joys.But we should not be sad, in fact the process of running after is more enjoyable and valuable than the final result, let＇s enjoy it! 相似文献
18.
Guoxiang Chi Pei Ni 《中国科技期刊研究》2007,23(1):33-37
The composition of fluid inclusions in the H2O-NaCl-CaCl2 system has been generally graphically estimated using the melting temperatures of hydrohalite （ Tm-HH ） and ice （ Tm-ice）. Here we present two equations that can be used to calculate the relative proportion of NaCl （ i. e. , NaCL/[ NaCl ＋ CaC12 ] , or XNacl ） and the total salinity （ i. e. , NaCl ＋ CaCl2, wt% ） for fluid inclusions with ice as the last melting phase. XNacl can be calculated from Tm-HH using the following equation： y = （a＋bx）^-1/c where y is XNacl, x is Tm_HH , a =0. 33124402, b =-0. 031518028, and c =0. 22932736. In the cases where only Tm-ice is measured and Tm-HH is not known, Tm-ice can be used as the maximum possible Tm-HH to calculate the maximum value of XNacl using the above equation. In these cases, the following equation can be used to calculate the maximum total salinity： y=（a＋bx＋cx2） l where y is salinity, x is Tm-HH , a =0, 057184817, b =0. 00078565757, and c = 5. 7262766E-6. Because the isothems in the field of ice are sub-parallel to the NaCl-CaCl2 binary side in the H2O-NaCl-CaCl2 ternary system, the errors in salinity calculation introduced by the above approximation are small （ less than 2 wt% ）. A Windows program for calculation of XNacl and salinity is available at ： http ：//uregina. ca/-chiguox. 相似文献
19.
Leonurus japonicus Houtt. [L. heterophyllus Sweet, L. artemisia (Lour.) S. Y.
Hu] is one of the most important traditional Chinese medicines used as a remedy for gynaeco-
logical disease since ancient times. A cytological investigation on the species was carried out
and the materials for chromosomal examination were collected from 26 localities in 20 provi-
noes and autonomous regions of this country. The number of chromosomes in root tip cell of
the species was found to be 20 on the whole (Tab. 1:1), agreeing with those reported by Ma and
al.[2] and probably by Chuang and al.[3] as well.
The genus Leonurus L. is variable in its chromosomes with an aneuploidy of x=9, 10 and
12. The present authors would propose that the primitive basic number of chromosome in the
genus is 9, and thus both 10 and 12 are derived, for: (1) among the 9 species (including 1 sub-
species) heretofore cytologically examined, x=9 occurring in 66.7%, x=10 occurring in 22.2%,
while x=12 occurring only in 11.1%; (2) in generaclosely related to the genus under considera-
tion, such as Panzeria, Galeobdolon and Lamium x=9 being the sole basic number.
But L. japonicus exhibits a mixoploidy of 2n=20 (occurring at the rate of 53.30% of the
total amount of cells examined), 2n=18 (30.70%), and 2n=16 (15.99%) in our work. (Table
1). Since the original basic number of chromosome of the genus is 9 as proposed above, 2n=
20 would be considered as a derived one and the occurrence of 2n=18 probably suggests an
early evolutionary trend of 2n=18→20 of the pecies in question. 相似文献
20.
《中国科学院院刊(英文版)》2004,18(4):232-234
A high-temperature & superconductor (HT-SC).magnetic levitation train has its merits shared by the conventional conductor type and the lowertemperature type of the maglev trains but hasn‘t the latter two‘s demerits. Its suspension height is 50mm and its technical norms about the smoothness on the roadbed and rail are much lower than those required by the conventional conductor maglev train. So, it is convenient to be introduced in a drive of largescale popularization. Its suspension could be maintained in a standstill state and no driving system is needed for the control of its suspension and alignment. 相似文献