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The present paper reports the first record of the genus Hymenopyramis in China.
H. cana is a new record on Hainan Island of Guangdong Province. It grows in deciduous mon-
soon forests or shrubby savanna (western Hainan) at 50 to 150 m alt. 相似文献
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微压力传感器主要用于测量气体或液体的微小压力 ,通常最小压力测量范围为 1ｋＰａ—1 0ｋＰａ ,在石化、冶金、电力、水文等行业中广泛用作压力、液位测量。此外 ,随着机电一体化及信息技术的发展 ,在空气动力装置、医疗、家电等领域也开始大量应用 ,其需求量逐年增长。目前国内外常用的微压力传感器主要有两种 ,一是扩散硅 ,二是组合式。量程一般在1 0ｋＰａ— 5 0ｋＰａ ,不耐腐蚀 ,成本高。要进一步提高灵敏度 ,向微压力品种发展 ,这两种结构的微压力传感器都存在相当大的难度。为研究开发新产品 ,在“九五”传感器国家重点科技攻关计划… 相似文献
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PECVD是太阳能电池制造过程中非常重要的工序,它的作用是在晶体硅表面形成一层起钝化和减反射作用的膜。本文主要研究SINA设备链式PECVD加热速率与膜厚、折射率之间的关系。通过调整PECVD工艺腔室三个温区的加热速率且在其它条件都不变化的前提下观察加热速率对膜厚、折射率两参数的影响,其结果为:加热速率越快折射率越高,膜厚越小。 相似文献
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对海信TLM3277液晶彩色电视机开关电源的构成及内部模块的功能和原理作了详细地说明和理论分析。 相似文献
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石铸 《中国科学院研究生院学报》1993,31(5):432-450
The Present paper is a preliminary result of study on three genera,
Dubyaea, Syncalathium and Soroseris of the tribe Lactuceae (Compositae) in China.
The genus Dubyaea in China so far known consists of 14 species, of which
six are described here as new: D. pteroponda Shih, D. lanceolate Shih, D.
muliensis Shih, D. panduriformis Shih, D. cymiformis Shih and D. jinyangensis
Shih. In addition, one new combination, i.e.D. bhotanica (Hutch.) Shih, is
made.
There are six species in the genus Syncalathium in Chinese flora, of which one
species is described here as new. This is S. orbiculariforme Shih. A new combina-
tion, S. pilosum (Hand.-Mazz.) Shih, is made in the paper.
The genus Soroseris comprises nine species, of which three are described here
as new, S. teres Shih, S. chrysocephala Shih and S. qinghaiensis Shih. Three new
combinations, i.e.S. trichocarpa (Franch.) Shih, S. hirsuta (Anth.) Shih, and S.erysimoides (Hand.-Mazz.) Shih are made in the present paper. 相似文献
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目前由厚膜材料制作的发热体在家用电器中广泛应用。本文主要对厚膜发热体的加热原理、材质、工艺、失效机理、相关计算等方面进行了较深入的研究,对厚膜发热体的设计、生产、应用等起到一定的指导作用。 相似文献
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为探讨厚壳树亚科在紫草科中的系统位置，用扫描电子显微镜研究了国产厚壳树亚科Ehretioideae的厚壳树属Ehretia、轮冠木属Rotula和基及树属 Carmona 3属12种植物的花粉形态，其扫描电镜资料属首次报道。从本文并结合文献报道的双柱紫草属 Coldenia的花粉资料，可得知该亚科花粉为长球形 、近球形，稀球形,赤道部位具有不同程度的膨大；萌发孔类型为三孔沟和三拟假沟二者交替排列，稀具三孔；外壁表面具微弱的小穿孔，稀光滑或皱波状纹饰。厚壳树亚科Ehretioideae与破布木亚科 相似文献
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The present paper is an attempt to throw some light on two Composite genera,
Cavea W. W. Smith et Small and Nannoglottis Maxim., of which the generic features
and the systematic position were heretofore rather badly known.
Cavea, a monotypic genus based upon Saussurea salwinensis Drumm., was described
by W. W. Smith and Small as monocious. From the ample material now in our com-
mand, it is found that the genus is either monocious and dioecious, the capitula in the
latter case being homogamous. The individuals exclusively provided with sterile flowers
are usually smaller in size, sometimes even stemless. Such repartition of sexes was
known in the subtribe Plucheinae (tribe Inuleae), to which W. W. Smith and Small were
correct to ascribe their genus.
Nannoglottis was considered by Maximovicz as un abnormal genus of the tribe
Inuleae, having heterogamous capitula with one series of peripheric fertile ligulate pistil-
late flowers. Having examined the type specimen of N. carpesioices Maxim. and the ex-
tensive collection from Kansu and Tsinghai, we incline to say that the genetic characters
as discerned by Maximovicz are doubtlessly due to his inaccurate observation. The
flowers of Nannoglottis are in fact trimorphous, of which the pistillate ones are 2-3-
seriate, the outer being shortly ligulate and the inner, short-tubulate with truncate apex.
Handel-Mazzetti, much later, indicated that, in another species, the pistillate flowers are
2-3-seriate, but no mention was made about the inner tubulate pistillate flowers.
Franchet, appearing to be unware of Maximovicz's genus, founded his Stereosanthus
Franch. and considered it as a genus intermediate between the tribes Inuleae and Sene-
cioneae. The genus was misinterpreted by Franchet as having dimorphous flowers, the
pistillate ones being all ligulate. Curious enough, one of the major generic features, viz.,
the presence of inner tubulate pistillate flowers, was neglected by all early botanists and
was first recognized by Handel-Mazzetti fourty years later.
However, Handel-Mazzetti was still unacquainted with the characters of Nannoglot-
tis and proposed therefore his new genus Vierhapperia Hand.-Mzt. on the reason that the
flowers are trimorphous. Moreover, he compared his genus with Conyza L. and Erigeron
L. of the tribe Astereae, but the characters marked by him appear not to be different
from those of Nannoglottis.
From the above morphological comparaison, it is evident that Nannoglottis and two
other genera in question possess in common important characters in the general appea-
rance, the flower-forms and the structure of achenes and pappus. The differences in the
disposition of involucral bracts and the length of ligules are criteria good for separating
species, but can hardly be regarded as sufficient for generic delimitation. Moreover,
these three genera are almost similar in their geographical distribution. These points are
adequate to warrant that Stereosanthus and Vierhapperia are in reality congeneric with
Nannoglottis.
Nannoglottis appears to have been correctly placed by Hoffmann in the subtribe
Senecioninae (tribe Senecioneae) though in that subtribe it finds no close relatives. On
account of the outstanding characters of the genus, a further study of its systematic posi-
tion is required.
The present paper is brought to close by a tentative scheme of classification of the
genus so amplified, of which two sections, namely, sect. Stenolepis Ling et Y. L. Chen
(Stereosanthus Franch., p. p. min.) and sect. Nannoglottis (Stereosanthus Franch., p. p.maxim.; Vierhapperia Hand.-Mzt.), altogether including 9 species, are being proposed. 相似文献
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为了研究含壁厚不均和壁厚减薄缺陷储气井的疲劳寿命,利用nCode软件计算了12种壁厚不均缺陷和13种壁厚减薄量缺陷下储气井井筒的疲劳寿命,得到了壁厚不均差值δ和不同壁厚减薄量e改变对储气井井筒高、中、低压组疲劳寿命的影响。研究结果表明:(1)含壁厚不均缺陷井筒的疲劳寿命最低点出现在套管与管箍连接部分第一个螺纹的根部,且疲劳寿命随δ的增加而减小。储气井井筒高、中、低压组满足行业标准的δ临界值为2.0、1.95 mm和1.9 mm。(2)当e≤2.5 mm时,含缺陷的储气井井筒的最低疲劳寿命点出现在套管与管箍连接部分第一个螺纹的根部,壁厚减薄对储气井的疲劳寿命没有影响。当e≥2.5 mm,含缺陷的储气井井筒的最低疲劳寿命点出现减薄区域的套管内壁。储气井高、中、低压组井筒满足行业标准的e临界值为4.05、3.95 mm和3.85 mm。 相似文献
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林镕 《中国科学院研究生院学报》1965,10(1):75-90
The present paper concerns itself with three Composite genera of the tribe Cynareae
(subtribe Carduinae), Vladimiria Ilj., Diplazoptilon Ling and Dolomiaea DC., all ranging
throughout the Sino-himalayan region, These genera have in the past always been as-
sociated with the Eurasiatic genus Jurinea Cass., though there is hardly anything that
can indicate such a relationship. Jurinea, according to the conception of Iljin, is a clearly
deliminated natural genus, while the three genera now in question are all closely allied to
Saussurea DC., being quite remote from Jurinea in the corolla forms, the structure of
receptacle and pappus, and also in the morphology of pollen grains.
Vladimiria was founded by Iljin, based on Jurinea salwinensis Hand.-Mzt. The
genus is a close relative of Saussurea from which it differs chiefly in the usually many
seriate pappus which are composed of scabrous or partly barbellulate bristles. As a re-
sult of our study, a tentative scheme of classification is here proposed, in which Iljin's
original generic concept has been amplified to include a dozen of species previously re-
ferred to Jurinea by Franchet, Diels, Anthony and Handel-Mazzetti from the flora of
south-western China and adjacent countries. Two sections, namely, sect. Sorocephalos
Ling and sect. Vladimiria (Saussurea sect. Carduella Franch., Mazzettia Ilj.), are being
proposed.
Diplazoptilon, a new monotypic genus based upon Jurinea picridifolia Hand.-Mzt.,
is here proposed. It occupies an intermediate position between Vladimiria and Saussurea
with a closer affinity to the former, from both of which it is, however, distinguished
chiefly by the biseriate pappus with equal plumose bristles.
Dolomiaea, a natural genus early founded by De Candolle on the basis of the Hima-
layan D. macrocephala DC., was considered by Bentham and Hooker f. as not different
from Jurinea, a treatment having being followed since by most botanists of the past.
But, as mentioned above, its relationship with Saussurea is obvious. It seems to differ
from that genus in the two to many seriate pappus, consisting of numerous barbellulate
bristles, and in the short style branches. In view of its affinity with Saussurea rather
than with Jurinea, the generic status of Dolomiaea should be maintained accordingly. As
construed above, the genus is now represented by about 5 species, most of which werepreviously referred to Jurinea by different botanists. 相似文献
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向秋云 《中国科学院研究生院学报》1987,25(2):125-131
Cornus L. s. 1. is a large polytypic genus. The classificantion of which has been
so different that some authors recognize several separate genera, while others treat them as ei-
ther subgenera or sections. New evidence from many disciplines such as palynology, cyto-
logy, wood anatomy and embryology supports the view that the genus should remain in the
broad sense. I basically agree with the treatment by Ferguson (1966b) before my finishing
a comprehensive study on Cornus L. s. 1. except for supporting the separation of subgenus
Afrocrania as an independent genus. A new subgenus Sinocornus Q. Y. Xiang, containing
one species, C. chinensis Wangerin, is established here on account of its inflorescence axillary
and different from the other members of the genus which all have terminal inflorescences only.
The inflorescence developed from a terminal bud implicates the sympodial nature of axis of
stem and the one from an axillary bud the monopodial one. It is reasonable to regard the
character as of subgeneric value. Also a new combination, Cornus subgen. Syncarpea (Na-
kai) Q. Y. Xiang, is proposed here as a substitute for Cornus subgen. Benthamia (C. B. Clar-
ke) Schneider used for a long time. Because the valid publication of the former name subgen.
Syncarpea Nakai is earlier than the latter one. The types of inflorescences of 8 subgenera re-
presented by type or selected species are illustrated. 相似文献