concrete _生活经验

“砼”怎么读？什么意思？砼
拼音：tóng注音：ㄊㄨㄥˊ

部首:石,部外笔画:5,总笔画:10

五笔86&98:DWAG仓颉:MROM郑码:GOBI

笔顺编号:1325134121四角号码:18612UniCode:CJK 统一汉字U+783C

基本字义

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● 砼

tóngㄊㄨㄥˊ

◎ 混凝土。

English

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concrete

英文里描述一个人在某方面有concrete experience,这里的concrete怎么翻译比较好?你好，希望翻译能够给你帮助。如果有差错请见谅。首先看一下concrete单独使用的意思：

A.

1. 有形的;具象的;具体的
2.. 混凝土的
n.[U]
1. 具体物
2. 混凝土
v
1. 使凝固;使结合
2. 用混凝土修筑;浇混凝土于
3. 凝结,固结
而这样描述esperience可以解释为坚实的，具体的经验。

mass concrete怎么读mass concrete
[英][mæs ˈkɔnkri:t][美][mæs kɑnˈkrit]
大体积混凝土，大块混凝土;
Crack-control for construction of mass concrete in Jinhua square item
金华广场项目大体积混凝土施工中裂缝的控制

“砼”潮汕话怎么读音tóng，混凝土的同意词。在工程设计和施工中，经常把“混凝土”三个字简写为“砼” 。

字形结构
汉字首尾分解：石工
汉字部件分解：石人工
笔顺编号：1 3 2 5 1 3 4 1 2 1
笔顺读写：横撇竖横折横撇捺横竖横[1]

部首笔画
部首：石
部外笔画：5
总笔画：10
五笔86：dwag
五笔98：dwag
仓颉mrom
四角号码: 18612
郑码: gobi
Unicode: CJK 统一汉字 U+783C

考研英语和四级英语词汇一样吗

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考研英语在词汇上主要考察熟词僻义，有些中学词汇的新用法都能考的一塌糊涂；四、六级英语主要考察生词的第一意义或常用意义，只要你背了大纲的词汇表，基本就没问题。英语四级CET4考试入场前须知：1、考试前，请各位考生务必检查自己的耳机，以确保其能正常使用，并准备好足够的电池!考场不提供无线耳机和电池。2、请各位考生妥善保管好准考证，遗失不补!3、准考证、学生证和身份证三证齐全方可进入考场。有遗失学生证或身份证者，请到所在系行政秘书兼辅导员处开具证明。无准考证或学生证、身份证两证均遗失者不得参加考试。
考研英语需要掌握多少词汇？词汇量这个东西没有一个固定的说法，不过考研英语大纲要求的词汇量是5500个。考研英语的水平提高，报课阿卡索的英语课程是一个不错的选择，建议你可以抓紧是报课学习。【https://www.acadsoc.com】点击蓝字即可免费领取欧美真人外教一对一免费试听课！阿卡索的英语课程拥有较高的性价比，每节课不超过20元，平民化的价格致力于让每一个学员都能享受到高品质的在线英语课程，外教执教经验丰富，能够针对不同基础和水平的学员制定相应的教学方案，满足多样化学习需求。大家想要找到合适英语培训机构，百度搜下【阿卡索vivi老师】即可。百度搜下【阿卡索官网论坛】免费获取全网最齐全的英语资源。
2015考研英语大纲词汇一共多少个

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大纲词汇表中的单词数量没有发生变化，还是5500个。词汇：考生应能掌握5 500左右的词汇以及相关词组。除掌握词汇的基本含义外，考生还应掌握词汇之间的词义关系，如同义词、近义词、反义词等；掌握词汇之间的搭配关系，如动词与介词、形容词与介词、形容词与名词等；掌握词汇生成的基本知识，如词源、词根、词缀等。英语语言的演化是一个世界范围内的动态发展过程，它受到科技发展和社会进步的影响。这意味着需要对本大纲词汇表不断进行研究和定期的修订。此外，全国硕士研究生入学英语统一考试是为非英语专业考生设置的。考虑到交际的需要，考生还应自行掌握与本人工作或专业相关的词汇，以及涉及个人好恶、生活习惯和宗教信仰等方面的词汇。扩展资料：英语考试是为高等学校和科研院所招收硕士研究生而设置的具有选拔性质的全国统一入学考试科目，其目的是科学、公平、有效地测试考生对英语语言的运用能力，评价的标准是高等学校非英语专业本科毕业生所能达到的及格或及格以上水平，以保证被录取者具有一定的英语水平，并有利于各高等学校和科研院所在专业上择优选拔。参考资料：百度百科——英语考研大纲
考研英语单词大概需要背多长时间第一个阶段，3-6月份，是打词汇基础的时间，这段时间要集中记忆考研大纲词汇5500的基础词汇和高频词汇。
第二个阶段，7-12月份，在真题中查漏补缺自己的词汇量，且着手记忆一些低频的，但是也比较实用的词汇。

concrete是什么意思？concrete
adj. 混凝土的；实在的，具体的；有形的
vi. 凝结
vt. 使凝固；用混凝土修筑
n. 具体物；凝结物

concrete，specific都是是具体的意思，怎么区别解释1.[concrete;specific] 不抽象,不笼统,细节很明确。例如：说得很具体/具体计划。2.特定的。例如：具体的人/你担任什么具体工作？3.把理论或原则结合到特定的人或事物上（后面带“到”）。近义词：详细、周密、细致、详尽反义词：抽象、模糊、笼统三个都可以如：详细对具体正如简略对抽象。

concrete class是什么意思concrete class
可继承实体类；具体类；可继承具体类
例句筛选
1.
Using one data entity per concrete class
每个具体类使用一个数据实体
2.
However, you must map the fields for each concrete class.
但是，必须映射每个具体类的字段。

concrete poetry是什么意思concrete poetry
有形诗；图像诗（等于concretism）
This paper mainly discusses iconicity on textual level and exposes its function in concrete poetry cohesion and coherence.
从语篇层面可以揭示象似性在视觉诗语篇街接与连贯中的重要作用。

on the concrete是什么意思On the concrete
在这水泥地上
双语例句
Otherwise, you may be better off on the concrete.
不然的话，你还不如去跑混凝土路。

c++问题，求高手私有成员只作用在类范围内有效，要想在别的函数调用他，的通过类中函数去间接调用它。他的生存期从占用内存开始，到析构函数调用后。

翻译句子Steering the concept of the Steering manufacturing products / or providing services for the management staff of people. 2, the steering role as a supervisor, you have to branch offices, customers and employees fulfill their obligations, This is a nexus under your position. As for your employees, you represent management, power, direction, discipline, vacation time, increased revenue and promotion. Right branches or your superiors, you are with the staff and their specific link between the work. You represent the productivity, cost, artificial efficiency, quality management, customer service; while you proceed on behalf of the staff under the needs and requirements. Right customers, your products and staff representatives to the entire company. 3, supervisor of the obligations branches obligations : A. this area, which related to their interests. They are also the reasons for your employment. B. Steering obligation efficient completion of the work authorized agents. C. As with the staff and the day-to-day contact with clients more frequently, supervisors also have an obligation of staff, Customer demands reported to the agents.  obligations to clients : A. store opened to help the whole process. B. the day-to-day operational management support (people, goods, and so on). C. franchise business daily training assistance. Obligations to employees :  to create a staff making them feel that they have been accepted, and to be recognized and to the relative candor, with fairness, a sense of open work atmosphere. The majority of today's employees, the previous hardline Hypertension Management Act has no effect. They can create a you are willing to pay for the work atmosphere is not only your right to their obligations, as well as the needs of their own work.

c++中 “类名对象名(数据成员初始化 )”是什么意思和作用class person{public:string name;person(string n){name = n;}};person p("张三");其中person为类名， p为对象名，"张三"为给构造函数（person::person()）的参数

谁能帮我找份关于耐火混凝土的英文资料？？Dry phosphate refractory concrete materials
Abstract

The present invention is directed to a dry phosphate cement mixture and process for manufacture of same. The dry mixture includes at least Al(H2 PO4)3, a group IIA metal bonded to oxygen, and an aggregate. The process for manufacturing cement includes associating the dry reagent with a substantially polar solvent, such as water. The total reagent concentration is formulated such that only nominally exothermic reactions are observed. The process accommodates variable setting times and provides resulting concrete which exhibits formidable structural integrity.

Claims

What is claimed:

1. A refractory cement mixture comprising a dry reagent composition including:

at least one oxide of an element belonging to group IIA of the periodic table present in an amount of 0.5 to 2.0 percent by weight of the dry reagent composition;

Al(H2PO4)3 ; and

at least one aggregate, wherein the aggregate is selected from the group consisting of olivine, silica, aluminum oxide, kyanite and bauxite.

2. The refractory cement mixture according to claim 1, further including an aqueous medium.

3. The refractory cement mixture according to claim 2, wherein the aqueous medium consists of a polar solution.

4. The refractory cement mixture according to claim 1, wherein the Al(H2 PO4)3 is present in an amount of about 2.2 to 7.3 percent by weight of the total dry reagent composition.

5. The refractory cement mixture according to claim 1, wherein the at least one aggregate is present in the amount of from about 75 to 95 percent by weight of the dry reagent concentration.

6. The refractory cement mixture according to claim 1, wherein the group IIA oxide has a particle size range from minus twelve to positive three hundred mesh.

7. The refractory cement mixture according to claim 1, wherein the group IIA oxide comprises MgO.

8. A process for manufacturing refractory cement comprising:

dry mixing active reagents so as to form a dry reagent composition, wherein the active reagents include:

at least one oxide of an element belonging to group IIA of the period table present in the amount of 0.5 to 2.0;

Al(H2 PO4)3 ; and

at least one aggregate, wherein the aggregate is selected from the group consisting of olivine, silica, aluminum oxide, kyanite and bauxite.

9. The process according to claim 8, wherein the Al(H2 PO4)3 is present in an amount of about 2.2 to 7.3 percent by weight of the total dry reagent composition.

10. The process according to claim 9, further comprising the steps of:

charging water into the dry mixture of active reagents and an aggregate such that an aqueous mixture is synthesized during a exothermic reaction; and

curing the resulting aqueous mixture.

11. The process according to claim 10, further comprising the step of:

varying the amount of one or both of the oxide of an element belonging to group IIA of the periodic table or the Al(OH2 PO4)3 to, in turn, adjust the curing time of the resulting aqueous mixture.

12. The process according to claim 8, further comprising the steps of:

charging water into the dry mixture of active reagents and an aggregate such that an aqueous mixture is synthesized during an exothermic reaction; and

curing the resulting aqueous mixture.

13. The process according to claim 12, wherein the process further comprises the step of:

varying the concentration of one or both of the oxide of an element belonging to group IIA of the periodic table or the Al(H2 PO4)3 to, in turn, adjust the curing time of the resulting aqueous mixture.

14. The process according to claim 10 wherein the active reagents have a particle size and the curing time of the aqueous mixture is varied by varying the particle size of one of the reagents.

15. The process according to claim 12 wherein the active reagents have a particle size and the curing time of the aqueous mixture is varied by varying the particle size of on of the reagents.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to dry phosphate refractory concrete materials having MgO and AI(H2 PO4)3, and more particularly, to special compositions which when synthesized yield nominally exothermic reactions, and use virtually "catalytic" amounts of active materials without sacrificing either structural integrity or variable setting times.

2. Background Art

Refractory concretes, also known as castables, are normally bonded with high-temperature calcium aluminate cement. Cement adlevels commonly range from one to forty percent and setting times are typically variable and range from 30 minutes to over 3 hours. In some instances, a fast setting time is desired, for example, when specialized manufacturing of uniquely-shaped burner block is desired, or, when rapid furnace repairs or patches are needed. Inasmuch as many thousands of dollars per hour are lost while a furnace is non-operational, minimizing such furnace down time is essential. Another example of when a fast set of the refractory material is desired is during the forming and pouring of furnace walls when construction time is extremely limited due to scheduling demands. Indeed, while accelerating the setting time of calcium aluminate concretes is known in the art, the ultimate structural integrity of the material does become adversely affected. Additionally, the initial dry-out and heat-up of the calcium aluminate concrete castable takes a substantial amount of time regardless of, and in addition to, the initial setting time of the mixture.

In addition to the above, safety must be considered when configuring a furnace heat-up schedule. For example, refractory calcium aluminate cement develops strength after hydrating the chemical reagents. Sufficient water must be charged to a cement-bonded high-temperature concrete to hydrate the cement and allow for placement and/or movement of the mass. After the cement-bonded concrete is hardened, the water must be removed slowly before the furnace can be put back into service. Consideration must be given to the permeability of the mass, dynamics of the cement phases and its hydration level. The end result is that heating rates for concrete cure can require up to several hundred hours to reach the furnace operating temperature. As the concrete is heated, the mass functions as a "leaky" autoclave. The pressure caused by the vaporization of the free water and steam released from the dehydration of the cement can be explosive, if the pressure exceeds the tensile strength of the castable. Even if the mass does not actually explode, rapid heating can cause internal cracking and damage that will shorten the ultimate life of the concrete material. This damage is known as thermal shock damage.

The long turn-around times for concrete furnace linings and possible thermal shock damage are just part of the problem associated with conventional refractory material. Indeed, if the furnace lining comes into contact with molten metal, an adverse chemical reaction can occur. This adverse reaction, as observed in calcium aluminate cement systems, is considered a weak link in the ability of refractory concretes to resist molten metal attack and/or penetration of the furnace lining.

Phosphate refractory concretes, on the other hand, have several advantages over traditional calcium aluminate cement-bonded products. The first benefit is that the phosphate bond is not affected by molten aluminum. The metal is non-reactive with the phosphate, unlike the calcium aluminate of traditional cements. Another benefit is curing or firing time. Phosphate-bonded materials generally can be heated much faster than traditional cement-bonded products. Furthermore, there is a much lower chance for sustaining thermal shock damage. Phosphate-bonded concretes use many different types of phosphates and often have a basic component such as magnesium oxide (MgO) which reacts with the phosphate in the presence of water (or an aqueous liquid) whereupon hardening occurs.

Although such conventional phosphate bonded concretes have exhibited various benefits over other conventional refractory materials, problems nevertheless persist. For example, when phosphate-bonded concretes are used, the reaction rate is often so fast that the concrete cannot be poured into place before it hardens. Additionally, when a liquid phosphate or phosphoric acid is used, safe handling of the toxic liquid presents a real hazard, not to mention the burden associated with working with a two-phase system.

Greger, U.S. Pat. No. 2,450,952 (hereinafter "Greger '952") appears to disclose a dry phosphate cement mixture for adhesive applications. The reagents used in Greger '952 included magnesia, olivine and or magnesium silicate mixed with water soluble aluminum phosphate. The weight ratio of the magnesium compound to the phosphate is disclosed to be 2:1 to 8:1. Inasmuch as the set is relatively fast when magnesia is used as a reagent, Greger '952, discloses substituting olivine for the magnesia, to, in turn, slow the set time for as much as 24 hours. However, olivine has limited high temperature applications due to melting point considerations and chemical reactivity at high temperature.

Tomic, U.S. Pat. No. 4,392,174 (hereinafter "Tomic '174") appears to disclose a mixture of magnesium oxide in aluminum phosphates, as well as using aluminum phosphates in liquid form. Aggregates, such as gravel or trap rock are combined with a mixture of magnesium oxide and phosphate, and then used for such applications as patching of highways. However, Tomic '174 teaches the use of high magnesium oxide concentration (as well as other high reagent concentrations). Although such a high concentration appears to provide a phosphate cement with great structural integrity, the percent composition of the active reagents is undesirably high. The result of having such high concentrations of active reagents is that undesirable levels of heat are generated as a result of the exothermic nature of the chemical reaction. Furthermore, the cost of the active reagents in phosphate concretes are quite expensive when compared to the cost of the inactive reagents. When used in such great concentrations, as taught in Tomic '174, the profitability of an installation is adversely affected.

It is thus an object of the present invention to provide a dry phosphate refractory concrete which can be synthesized in a cost effective manner.

It is a further object of the present invention to provide chemical compositions, such that when synthesized, liberate nominally exothermic properties.

It is yet a further object of the present invention to provide phosphate concretes as described above, without sacrificing structural integrity or the necessary enhancement of variable setting times.

More particularly, it is an object of the present invention that regardless of the specific active reagent concentrations (such as those experimentally identified in the present disclosure, relative to the present invention), other reagent concentrations less than conventionally known, and, which, in such relatively low concentration result in hardened refractory material maintaining excellent structural characteristics, are likewise fundamental to the objective parameters of the present invention.

SUMMARY OF THE INVENTION

The present invention is directed to a cement mix comprising: a dry reagent composition including; at least one active dry reagent selected from the group consisting of group IIA elements associated with oxygen, and another active dry reagent comprising Al(H2 PO4)3, wherein the concentration of the group IIA oxide ranges from about 0.5 to 2.0 percent by weight of the total dry reagent composition; and at least one aggregate.

In a preferred embodiment of the invention, the cement mix further includes an aqueous medium. Additionally, it is contemplated that the aqueous medium is substantially polar.

In another preferred embodiment of the invention, the aggregate is selected from at least one of the group consisting of Olivine, Kyanite, Silica, Bauxite, Aluminum oxide and minerals or synthesized derivatives thereof.

In yet another preferred embodiment of the invention, the group IIA oxide includes MgO. The invention further contemplates that the MgO has a distribution range from minus twelve to positive three hundred mesh. Moreover, the invention contemplates that the Al(H2 PO4)3 concentration ranges from about 2.2 to 7.3 percent, and the at least one aggregate concentration ranges from about 75 to 95 percent by weight of the total dry reagent composition.

The present invention is also directed to a process for manufacturing cement comprising the steps of: a) dry mixing active reagents, wherein the active reagents includes; at least one active dry reagent selected from the group consisting of group IIA elements associated with oxygen, and another active dry reagent comprising Al(H2 PO4)3, wherein the concentration of the group IIA oxide ranges from about 0.5 to 2.0 percent by weight of the total dry reagent composition; and at least one aggregate; b) charging an aqueous medium into the dry mix active reagents and aggregates, wherein the step of charging includes maintaining a net active reagent concentration equal to or less than the necessary concentration for observing nominally exothermic synthesis, to in turn, result in an aqueous mixture; and c) setting the resulting aqueous mixture.

In a preferred embodiment of the invention, the process further comprises the step of varying setting times of the resulting aqueous mixture. Moreover, the invention contemplates that the step of varying setting time comprises altering one of at least the dry reagent composition concentrations and particle distribution range.

In another preferred embodiment of the process, the active reagent concentration of Al(H2 PO4)3 ranges from about 2.2 to 7.3 percent, and the at least one aggregate concentration ranges from about 75 to 95 percent by weight of the total dry reagent composition.

DETAILED DESCRIPTION

While this invention is susceptible of embodiment in many different forms, there is described in detail a specific embodiment with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiment described hereinbelow.

At the outset, when magnesium oxide and aluminum phosphate are charged with water, a well-known acid-base type reaction occurs. The concentration of magnesium oxide and its particle size generally determine the setting time of the concrete. The concentration of MgO and Al(H2 PO4)3 directly affects the exothermic magnitude of the chemical reaction. Indeed, when "non-catalytic" amounts of active reagents are used, a significant exothermic reaction is observed. Accordingly, in each experiment in the present invention, the peak exotherm was nominal as a result of the virtually "catalytic" amounts of active reagents. Dry phosphate concretes of high structural integrity were synthesized using significantly less MgO and Al(H2 PO4)3 than contemplated by the prior art (see, for example Tomic '174). Moreover, as shown in experiments one, two and five, variable set times were still maintained using such diminished concentrations of active reagents. Amazingly, even with virtually "catalytic" (limited) amounts of active reagents, the phosphate refractory concretes maintained a very high degree of structural integrity. In support of such an invention, several experiments were conducted. The results are summarized herein-below.

Specifically, seven experiments were conducted, wherein the following common experimental procedure was used:

First, the dry reagents, which include at least the aggregate, MgO, and Al(H2 PO4)3 in which the phosphorus pentoxide (P2 O5) concentration was approximately sixty percent, were charged into a reaction vessel. Second, the dry reagents were mixed via conventional agitation methods for approximately fifteen minutes. Third, the reaction vessel was charged with H2 O, which resulted in a "concrete" slurry that was agitated for an additional two minutes. Fourth, the "concrete" reaction mixture was set and cast, which provided suitable material for analytical testing. Next, test samples were analyzed primarily for structural integrity via cold crushing strength methods (CCS). Additionally, analytical test data relating to net structural composition was provided when applicable. These additional tests included compositional density (.rho.) and modulus of rupture (MOR).

EXPERIMENT NO. 1

In this experiment, the following dry reagents and their respective percent composition by weight were used:

______________________________________
Dry ReagentPercent Composition
______________________________________
Olivine90.11
Silica Fume4.95
Surfactant0.04
MgO0.55
Al(H2 PO4)3
2.20
Non-Wetting Agent
2.15
______________________________________

The olivine used in this experiment consisted primarily of four dimensionally different aggregates. The grain sizes of the respective primary aggregates included: 3×50 mesh, 16×70 mesh, 12×40 mesh and 140 mesh material. Furthermore, the chemical composition of the olivine used in this experiment was ninety percent forserite (2MgO.SiO2) and ten percent fayalite (Fe2 SiO2). Moreover, the silica fume used was approximately ninety-five percent silica (SiO2) and dimensionally less than one micron. The magnesite (MgO) was technical grade and processed from sea water which was then calcined in a shaft kiln. The grain size of the MgO was one hundred mesh. However, other particle sizes, such as positive three hundred mesh, are suitable for use as well. Anyone of a number of conventional non-wetting agents which are understood in the art can be used.

After following the experimental procedure (as previously described), 6.6% H2 O (by weight) was charged into the reaction vessel and a nominally exothermic reaction was observed. Thereafter, 2×2×2" cubes were formed via vibration casting. The chemical composition of the "concrete" in this experiment provided a hardening ("set") time of ninety minutes. Test data was then collected following conventional industrial method ASTM C133. The test results after drying for sixteen hours at 230° F. provided a compositional density (.rho.) of 158 pounds per cubic foot (pcf) and a MOR of 166 pounds per square inch (psi). After heating to 1,000° F. and holding the temperature constant for five hours, the MOR increased to 966 (psi), and the CCS was then measured at 3,925 (psi).

EXPERIMENT NO. 2

In this experiment, the following dry reagents and their respective percent composition by weight were used:

______________________________________
Dry ReagentPercent Composition
______________________________________
Bauxite8.48
60% Al2 O3 Aggregate
55.14
Bauxite Fines6.36
Kyanite4.24
Al2 O3
16.97
MgO1.59
Al(H2 PO4)3
5.62
Non-Wetting Agent
1.60
______________________________________

The bauxite used in this experiment was a South American bauxite and was elementally eighty-nine percent Al2 O3 and has a granular range from minus three to positive six mesh. The sixty percent Al2 O3 aggregate was supplied from C-E Minerals in Andersonville, Ga. and is also known commercially as Mulcoa-60. Furthermore, the Kyanite used in this experiment was supplied by Kyanite Mining

pmp是什么意思；pmpmp是什么意思？PMP有两种含义1．PMP认证—项目管理专业人士认证PMP多指美国项目管理协会（PMI）发起的PMP认证。即Project Management Professional项目管理专业人士的英文首字母缩写。PMP认证在全球200多个国家和地区使用，国家外国专家局组织报名和考试。2、材料—工业塑料PMP还指一种塑料制品原料，在工业制造方面有广泛应用。如：光学分析用试管、化妆品类的盖子、软管、实验器具、分析仪、LED模条等。
ps是什么意思gdp是什么意思ps是photoshop

domino是什么意思? domino tricks又是什么意思？domino英[ˈdɒmɪnəʊ]美[ˈdɑ:mənoʊ]
n.多米诺骨牌; 骨牌效应; 化妆斗篷面具;
多米诺技巧

45Si2MnTi是什么意思？45是什么意思？2是什么意思？45硅2锰钛是表示含硅量为万分之45的硅锰钛钢，钛是微量。
例如老规范GBJ10-89《混凝土结构设计规范》中规定的热轧Ⅳ级钢筋，（40Si2MnV）,(45Si2MnTi), (45SiMnV)，就是。强度标准值540N/mm².

控股是什么意思？绝对控股是什么意思？控股是指通过持有某一公司一定数量的股份，而对该公司进行控制的公司。控股公司按控股方式，分为纯粹控股公司和混合控股公司。纯粹控股公司不直接从事生产经营业务，只是凭借持有其他公司的股份，进行资本营运。混合控股公司除通过控股进行资本营运外，也从事一些生产经营业务。国有控股公司是指从事国有资本营运的纯粹控股公司和混合控股公司。国有控股公司是国家授权对一部分国有资产行使资产受益、重大决策和选择管理者等出资者权利的企业法人。参股公司是指母公司参股的企业以及全资子公司控股、参股的企业。
Java 中 newInstance 方法和 new 的区别是什么1.new 是java中的关键字，是创建一个新对象的关键字。用new这个关键字的话，是调用new指令创建一个对象，然后调用构造方法来初始化这个对象，如果反编译class的话，会看到一个Object obj=new Object();这种语句，会先调用new指令生成一个对象，然后调用dup来复制对象的引用，最后调用Object的构造方法。
2.newInstance 不是关键字，newInstance() 是java反射框架中类对象(Class)创建新对象的方法。在这个过程中，是先取了这个类的不带参数的构造方法，然后调用构造方法的newInstance来创建对象
名：Object java.lang.Class.newInstance();如:Class clazz = String.class;
Object newInstance = clazz.newInstance();
3.newInstance()也经常见于工厂设计模式中，在该模式中，共产类的该方法返回一个工厂bean 。
如： Factory factory = new Factory();
Object obj = factory.newInstance();
4.严格意义上来讲，这两者并没有可比较性，因为一个是java的关键字，有明确的用法和定义。一个是经常使用，但非标准的方法名称。

java 什么是 instance methodinstance method就是成员方法的意思，一般类里定义的常规方法都是成员方法。这些方法在调用的时候是需要构建实例（对象），然后通过实例来调用。区别于类方法（class method），不需要实例就能直接通过类名调用。

Java中Method[]是什么类型你这是通过java的反射机制获取一个类的方法，返回了一个Method类的数组，这个类是JDK自带的，不可能没有

java两个实体类转化问题假如
A 类里有 2个属性X 和 Y
B 类里有 3个属性 X ,Y,Z
你的意思是这2个类唯一的区别是 B比 A 多一个属性，你想批量的把A 的一个实例转换成 B 的一个实例是这个意思吧。
你可以写一个处理类
写一个方法接收一个A类对象和多处来的属性返回一个B类对象，麻烦就麻烦一次以后直接调用传里个A类得到个B类就可以直接用了
例如
publicB setXYZ( Aa, intz){
B b=new B();
b.setX(a.getX());
b.setY(a.getY());
b.setZ(z);
return b;
}

java反射中method类中的invoke方法是做什么的，他有什么作用？首先Method类代表一个方法，所以invoke（调用）就是调用Method类代表的方法。它可以让你实现动态调用，例如你可以动态的传人参数。下面是一个简单的例子。public class MethodTest{public static void main(String[] args){String [] names ={"tom","tim","allen","alice"};Class clazz = Test.class;try{Method method = clazz.getMethod("sayHi", String.class);for(String name:names)method.invoke(clazz.newInstance(),name);} catch (NoSuchMethodException e){e.printStackTrace();} catch (IllegalAccessException e){e.printStackTrace();} catch (IllegalArgumentException e){e.printStackTrace();} catch (InvocationTargetException e){e.printStackTrace();} catch (InstantiationException e){e.printStackTrace();}}}class Test{public void sayHi(String name){System.out.println("Hi "+name);}}

cement 和 concrete 都是水泥的意思可是有什么区别呢？

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cement 和 concrete 都是水泥的意思，但是含义用法等不完全相同。1、含义cement：水泥;胶合剂;胶接剂;粘固粉巩固;粘牢;（用水泥、胶等）粘结;在…上抹水泥concrete：具体的，有形的，实在的，实际的;固结成的，混凝土制的混凝土;具体物;（图案式）有形诗;〔建〕钢筋混凝土使凝固;用混凝土修筑;萃取凝固;固结;变坚固;使用混凝土2、变换形式concrete：第三人称单数： concretes，复数： concretes，现在分词： concreting ，过去式： concretedcement：第三人称单数： cements ，现在分词： cementing，过去式： cemented ，过去分词： cemented3、用法concrete：用作名词：混凝土 building material that is made by mixing together cement , sand, small stones and water 用作动词：用混凝土覆盖 to cover sth with concretecement：用作名词：水泥 a grey powder made by burning clay and lime that sets hard when it is mixed with water. Cement is used in building to stick bricks together and to make very hard surfaces胶合剂；胶接剂；黏固剂 a soft substance that becomes hard when dry and is used forsticking things together or filling in holes共同利益联合起来的纽带，凝聚力 something that unites people in a common interest用作动词：用水泥、胶等粘结，胶合 to join two things together using cement , glue, etc加强，巩固（关系等） to make a relationship, an agreement, etc. stronger4、英语释义concrete：① a strong hard building material composed of sand and gravel and cement and water一种坚硬的建筑材料，由砂、砾石、水泥和水组成。② form into a solid mass 形成固体③ capable of being perceived by the senses 能够被感觉到的④ formed by the coalescence of particles 由微粒聚结形成cement：① a specialized bony substance covering the root of a tooth覆盖牙齿根部的一种特殊的骨质物质。② something that hardens to act as adhesive material变硬的东西，起粘合材料的作用③a building material that is a powder made of a mixture of calcined limestone and clay由煅烧石灰石和粘土混合制成的粉末状建筑材料。④ bind or join with or as if with cement用水泥粘合或接合
concrete cement有什么区别吗混凝土和水泥的区别

请教各位高人cement silo是水泥仓的意思么？水泥仓，水泥筒仓，是搅拌站、搅拌楼及其他各类设备的粉料存储配套装置

scement这个英文是什么意思?怎么读？没有scement这个单词，
是不是写错了？

有cement.vt.巩固，加强

水泥32.5a与水泥32.5b有什么区别是指矿渣硅酸盐水泥中矿渣的含量A类不大于50%;B类不大于70% 。普通硅酸盐水泥是没有字母代号的。一般使用A，装饰使用B. 水泥32.5A与水泥32.5B是指矿渣的含量A类不大于50%；B类不大于70%，一般使用A，装饰使用B.

start a concrete transaction 是什么意思开始一笔有形的/混凝土交易。
具体是哪个得从上下文分析。

arm's length transaction 的中文意思arm's length transaction 公平交易、正常交易（arm's length 是个词组）
rent-yielding assets 利好资产，盈利资产
impacted information 密集情报，压缩信息。

transaction是什么意思？为了完成对数据的操作，企业应用经常要求并发访问在多个构件之间共享的数据。这些应用在下列条件下应该维护数据的完整性(由应用的商务规则来定义):

分布式访问一个单独的数据资源，以及从一个单独的应用构件访问分布式资源。
在这种情况，可能要求在(分布式)资源上的一组操作被当作一个工作单元(unit) 。在一个工作单元中, 操作的所有部分一起成功或失败并恢复。在下面的情况下这个问题更加复杂:

通过一组分布式的、访问多个资源的数据的构件实现一个工作单元，和/或部分操作是被顺序执行的或在要求协调和/或同步的并行线程中。

在所有情况下, 都要求应用维护一个工作单元的成功或失败。在失败的情况下，所有资源要把数据状态返回到以前的状态
(比如说，工作单元开始前的状态) 。
事务的概念和和事务管理器(或者一个事务处理服务)在一个工作单元中的维护数据完整性，这就简化了这样的企业级别分布式应用的构造。

一个事务是有下列属性的一个工作单元:

原子性(ATOMICITY):
一个事务要被完全的无二义性的做完或撤消。在任何操作出现一个错误的情况下，构成事务的所有操作的效果必须被撤消，数据应被回滚到以前的状态。

一致性(CONSISTENCY):
一个事务应该保护所有定义在数据上的不变的属性(例如完整性约束) 。在完成了一个成功的事务时，数据应处于一致的状态。换句话说，一个事务应该把系统从一个一致-状态转换到另一个一致状态。举个例子，在关系数据库的情况下，
一个一致的事务将保护定义在数据上的所有完整性约束。

隔离性(ISOLATION):
在同一个环境中可能有多个事务并发执行，而每个事务都应表现为独立执行。串行的执行一系列事务的效果应该同于并发的执行它们。这要求两件事:

在一个事务执行过程中，数据的中间的(可能不一致)状态不应该被暴露给所有的其他事务。
两个并发的事务应该不能操作同一项数据。数据库管理系统通常使用锁来实现这个特征。

持久性(DURABILITY):
一个被完成的事务的效果应该是持久的。

かんだなつみです! 请问中文意思是什么？意思是：我是“神田なつみ”

【かんだなつみ】是个名字，还是个女性名字，【かんだ】是神田，是姓，后面的名字【なつみ】的日语假名有很多同音不同字的名字，有【夏海、夏见、夏実、夏美、奈津美、奈津実】等等。所以这个名字真要全部用汉字体现出来的话，大概有以下这些表示：

神田夏海
神田夏见
神田夏実
神田夏美
神田奈津美
神田奈津実

这中文意思是什么？蚕丝蛋白紧致面膜
适合所有皮肤类型
一片装

望采纳，谢谢！

怎么学习外语？一天因该至少学几个小时？语言学习是循序渐进的一个过程捏，无论是汉语、英语、日语还是韩语等等的语言，都是需要听说读写不断的学习和练习加强的，一步登天是不可能的。当然如果说要为了出国还是国外出差或是其他一些个人因素什么的，在一定短时间内速成个基础交流的还是可以的，不过速成的语言学习，不但要自身的语感和语言天分很重要，而且还需要有正确良好的学习指导以及自身的刻苦和努力，总的来说，如果想要不用多看多练学好语言是不可能的，就算是我们的母语，我们也是因为天天说天天看还有课程上有老师指导才会交流这么顺畅；语言学习不同于其他理科课程，记着公式靠理解靠思维逻辑为主，勤能补拙，熟能生巧吧！至于LZ说一天该学多少个小时，这个不该有个定义，得看个人的学习方法、学习效率以及语言学习的语感和基础，有些人一天一小时都比别人一整天泡在书里学到的多，学习主要说的是一个学习的收获和效率，不要纠结于说一定或者应该学多少小时！不过说到底，学习还是要一步一个脚印积累不要急于求成，脚踏实地的总是没错的！以上纯属个人一些心得和建议！希望帮到你！

学习外语有什么好处!学好外语，说一口流利地道的外语，能提高就业竞争力！不管是在生活、旅游还是工作中，你都可以用到英语，百利无一害！发音准确，别人才能听懂你的话。对于没什么英语基础的人来说，可以试试阿卡索，能根据学员水平量身定制课程，更加具有针对性，有利于英语口语的提升。而且，外教老师来自以英语为母语的国家，100%有证，学的也放心。【免费外教一对一课程】阿卡索课程的优势如下：1.咱外教均有tesol证书，外教经验比较丰富，在官网也可以查到学历信息。2.固定外教一对一教学，课程根据学员的英语情况和需求来定制。3.在线学习，25分钟一节课，每天1节课，高频次学习方式，保证学习效果。如果你想要免费获取全网最齐全的英语资源，欢迎百度搜索：阿卡索官网论坛。专注于打造中国英语学习资源分享网站。内容十分丰富，包含少儿英语、英语口语听力、英语四六级、新概念、商务英语等免费资源下载。
高中生有必要学习第二外语么有必要。
第二语言（Second Language）指人们在获得第一语言以后再学习和使用的另一种语言。经常作为辅助性语言以及通用语。此外，第二语言亦可与第一语言并列为个人母语。第二语言的学习，往往可能是由于第一语言不再具有优势（社会变迁、政治目的等）。例如，加拿大普查即定义第一语言为“幼时初学之语言且持续使用”，人类最早学习的语言有可能丢失，是为一种语言替换，这种情形可能发生在孩童随着家庭徙居（因移民或国际认养）而进入一个全新的语言环境。
高中生在高中期间除了通过语文来学习中文之外，还需要学习英语。英语是现在世界上流通最广的一门语言。中文虽然是使用的人数最多的一种语言，但是是因为中国是人口大国的原因。学生在掌握外语学习的同时，也就具备了与不同语言的人群进行沟通的一门技能。

在外语学习中，如何正确认识英语的听说能力？如何有效实现？听说不分家，虽然在国内的某些英语考试里依然单独设置听力和口语考试，但在实际交流中，几乎不存在单方面说或听的情况。在锻炼听力和口语时，我基本上都以知名英语新闻媒体的视听资源、英美剧和英语电影为主要素材，用不同的方法进行练习。

如何做好“ 说”这一关：
1）语音语调（模仿）：
语音语调上要强调模仿纯正的英语母语国家人。语流、语速也要达到英语母语匀速讲话的标准。请老师纠音，多听原版录音带，多模仿。做跟读的练习。
2）词汇句型积累：
大家应该多注重句型的积累，多听英语原版新闻或看些电影电视剧。因为视觉听觉结合可以加深我们的记忆，我们可以用电影场景记忆的方法来学习英语听说。很多学员跟我说：“老师，我看过的电影美剧多了去了，为啥我还是不会说？”不能看了就完了，我们的目的不是看剧情，而是学语言，可以把你感兴趣的英文电影或剧集的一个片段找出来，用听力“输入”的方式，边看边做笔记，记下句型。并经常“输出”，把学会的句型变成自己的口语。
3）背诵与模仿：
学习初期应努力背诵所学的课文，例如我们在大学听说读写拔高用的国际教材interchange2、3，这个教材别小看了它，一些最常用的句型和词汇以及语法都集中在这里。加上是英语母语国家的精英语言教育者编写，权威性是毫无置疑的。这里我要强调大家选教材一定要用由英语母语国家人编写或审译过的教材，这样可以避免学到不地道的英文。千万不要轻视了背诵，通过背诵，很多东西就变成了你自己的。虽然看起来这背诵的办法有点愚，但多年的实践证明它对练好口语最有效。一些警句和成语要烂熟于胸。一些精彩的段落也要尽可能地背下来。坚持跟读，这对口语能力的提高非有用，其实根本不会花去大家多久的时间，每天花上10分钟跟读英文就可以了。贵在坚持。反复地朗读不仅对语音是个很好的练习，对文章的无意识记忆也大有益处。
4）丰富知识：
不断地丰富自己语言以外的相关知识。广博的知识是提高口语水平的重要基础。这就是为什么作为一名翻译要求“You have to know something about everything.”
5）口语实践：
很多人老是说没有语言环境为由而放弃听说的训练，其实并没有大家想的那么困难。在老师正确的方法的指导下进行实践可以少走一些弯路。大家在口语的训练方面可以学会“自言自语”，把学过的东西复述出来。自己给自己创造语言环境。

什么样性格的人适合学外语？【concrete】都说性格成就未来，性格本没有好坏之分，我们要怎么样来塑造才是关键，很多东西都是靠自己的努力去改变的，对于学习也是一样，如果觉得自己比较好动，那就要想法子让自己安静的坐下来看书，并不是不可能的事情，只要你想并且去做，你会发现自己也可以安静地坐着认真学习，下面就和广州新东方英语学校小编一起来探索一下吧。一位著名的心理学家认为，努力形成习惯，习惯养成性格。著名的科学家爱因斯坦则说:“智力上的成就依技于性格上的伟大。”我们相信人的性格井不像心理学家以为的那样.是绝对的内向型或外向型的。大多数人的性格处于中间状态，而外语学习本身也需要一种理想的精神状态，即性格倾向、个性特质和心理状态的理想结合。这种理想的结合就是理想的外语学习性格，它包括认知、情感和意志三种品质，现概述如下: (1)认知能力敏锐的观察，清晰的识别，良好的记性，严密的思考是学习外语的必要能力。除此之外.还要有一定怀疑精神和批判精神，才能在学习上不落俗套，保持长久的开放心态和吸收外来文化的能力。但最重要的是外语认知结构的建立，以及建立以后的顺应和同化。(2)怕感因素学习外语不仅意味着记忆和思考，而且意味着兴趣和习惯。情感丰富的人善于理解他人及其言语，也善于表达自我，故而听、说、读、写、译能力的提高，没有丰富的感情和合理的想象力是不可能的。在这里最值得注意的是同感理解和移情作用，不仅表现在人际交往中.而且在语言学习中也具有关键的作用。(3)意志品质惫志品质直接从思想感情通向行为.在外语学习中不仅体现为一般的所谓有信心、有恒心、有毅力、不怕失致、不怕丢人，而且表现为外语学习的主动性、计划性、持续性。意志品质的检验当然要顾及学习效果，但二者之间不应是机械的对应，因为学习一门外语和体育运动达标毕竟不同。总之，无论专家们的研究成果如何，不同的个性的确对外语学习会产生不同的影响。一般认为，良好的性格有助于外语学习，而外语学习的成功也会增强学习上的信心，进一步促进良好性格的形成和发展。关键字：