是哪个存储器的标识符。（ ）
ac是哪个存储器的标识符。（ ）
在第一个扫描周期接通可用于初始化子程序的特殊存储器位是0.1。( )
触点有常开触点和（ ）
语句表设计语言是由（ ）和操作数构成的。
功能块图属于plc程序设计语言中的一种。（ ）
在用户程序中，每个线圈可以使用无数次。
在梯形图上在左侧母线或线路分支点处初始装载一个常开触点，可用指令（ ）。
在梯形图中表示串联单个常开触点的是（ ）指令
在梯形图中表示联单个常闭触点的是（ ）指令
ld/ldn指令既可用于与输入公共母线相联的接点，也可用于分支回路的开头。
电路块根据触点的连接情况的不同可分为串联电路块和（ ）电路块。 a.串联 b.混联 c.并联 d.以上均可以
并联电路块与前面电路串联时，使用（ ）指令。 a.ald b.old c.an d. on
ald和old指令无操作数。
逻辑堆栈指令包括：lps、（ ）、lpp a.lcd b.lfp c.lrd d. lan
逻辑进站指令即（ ）用于梯形图分支电路的开始 a.lps b.lrd c.lpp
lps和lpp指令必须成对使用，lrd指令有时可能不用
逻辑堆栈指令可以嵌套使用，最多为8层。
lrd指令把逻辑堆栈第一层的值复制到栈顶，2-9层数据不变，堆栈没有压入和弹出。
定时器按照工作方式可分为（ ） a.ton、tonr b.tonr 、tof c. ton、tonr 、tof
plc的时基脉冲按照周期分为1ms、10ms和（ ） a.100ms b.1000ms c.10000ms
定时器的定时时间=( ）×时基。 a.当前值 b.预置值 c.有效值 d.固定值
每个定时器可提供无数对常开和常闭触点。
在同一个程序中，ton和tof可以使用相同的编号。
计数器是对（ ）或由程序产生的脉冲进行计数的。 a.内部输入 b.外部输入 c.内部时钟 d.外部时钟
西门子s7-200系列plc提供三种计数器，分别是（ ） a.ctu b.ctd c.ctud d.以上都是
如果将计数器的（ ）作为复位输入信号，可实现循环计数。 a.常开触点 b.常闭触点 c.输入端 d.复位端
每个计数器可提供无数对常开和常闭触点供编程使用。
增计数器的输入端计数脉冲由低到高变化。
在同一个程序中，可以使用相同的计数器编号。
在plc运行时，总为on的特殊存储器位是 （ ） a 1.0 b 0.1 c 0.0 d 1.1
在第一个扫描周期接通可用于初始化子程序的特殊存储器位是0.1。
in a standard format of business email,s we are not necessary to begin with ___ according to the video.
what principle does a subject should follow according to the video?
which of the following closing massage is the most formal one?
we would like to invite you to an inspection tour to our ________ opened asian branch in shanghai.
you are always a ________ customer of our company, and your presence will definitely make the occasion more successful.
please confirm your attendance ________ by july 20, 2009.
this letter is used to appreciate the performance done in business which is mutually _______.
we all look forward to a long and ________ relationship.
your hard work on publicity and press arrangements was most ________.
on behalf of ncl association i wish to thank you for your ________ speech at our annual conference.
thank-you letters should be sent in a ________ manner.
my presentation skills allow me to communicate ________ with directors, as well as keep my team up to date on our progress.
the subject needs to be concise.
when it comes to your professional image, a sloppily composed email can do more damage than a weak handshake or a wrinkled suit.
we can use “good morning” or “good afternoon” in the beginning of an email as salutation.
emails are quite private and confidential.
in business email, it is typical to have your title closely after your name, which implies your authority.
as with any piece of business writing, you don’t need proofreading when you finish writing emails.
it is rare to see the big part of privacy notice in the end of emails.
emails allow us to keep projects moving when our co-workers are unavailable or on the other side of the world.
when writing business emails, you are encouraged to use abbreviations, slangs, emojis, and multiple exclamation points.
it is very common to have your way of contact and company website address in the signature part of your email.
we avail ourselves___ this opportunity ___approach you ___the establishment of trade relations with you.
our products enjoy____in the world market.
we have been informed that you are ____ the market____textiles.
which website in the following does not belong to b2b platform?
we take pleasure in enclosing a copy of your latest catalogue____for in our letter dated december 11.
we owe your name and address____the chamber of commerce of shanghai.
we if you could give us whatever information you can in this respect.
we shall do every thing possible to assist you a mutually beneficial trade.
in the following, which statements belong to the good tips for drafting a successful initial letter or email?
the basic structure of drafting an initial letter includes: ___________
the purpose of establishing business relations includes seeking new customers, consolidating existing relations and expanding new markets.
the chamber of commerce is an organization of business people that promotes international commercial interests.
the initial letter does not refer to the letter of establishing business relations.
“we specialize in this field for 12 years, with the strength of producing sneakers, which are superior quality with competitive price.” this sentence can be translated as: 我们在此行业已经营12年，我们生产的运动鞋物美价廉。
when we draft an initial letter, we must introduce our own company first.
the letter we sent 2 days ago is an enquiry____color tv sets.
there is steady demand here____leather gloves of high quality.
we would be pleased to send you some samples of our new cell phones on approval,____our own expense.
please____to let us have your offer as soon as possible.
do enquiry carry legal force for the seller?
if you receive an unfavorable reply to your enquiry, you’d better____.
____your prices are right, you will find a ready market in our market.
we can make an enquiry by______
the specific enquiry may include
there are many types of enquiry including_______
an enquiry is a request from the buyer for information on the supply of certain goods with engagement.
when we make an enquiry, we will surely receive a response from the customer.
we can make an enquiry by phone, email and fax.
in a letter of specific enquiry, it’s not necessary for the buyer to indicate the name of the goods he wants to buy.
sometimes general enquiry can be an initial letter.
we cannot our offer open for more than 3 days, so would you please telex your acceptance without delay.
we would make you the following offer, subject to your telex acceptance us not later than june 30, 1998.
if we had been informed in time, we the goods for you.
owing to all quantity required this time, we have refrained a counter-offer.
we regret to say that the prices you have bid are too low to .
who is an offeree?
_____of your offer would make your bicycles uncompetitive with other stores in our region.
we are not in a____to accept your bid at the present state of the market.
a satisfactory offer may include:
the content of counter offer may include:
quotation is a kind of firm offer.
if the buyer alters the contents of firm offer, then the firm offer will become invalid.
when the buyer provides their own price, we call it “bid the price”.
non-firm offers are not binding upon the sellers and the details of the offers may change at any time.
an expression of thanks needn’t be given if the offer is not acceptable.
please ship the ten chests of tea_____our order no. 2213 at an early date.
we thank you for your letter of may 5,_____ your purchase from us of 200 metric tons of peanuts.
we are pleased to_____the following transactions with you.
we are pleased that we have booked_____ 2000 pieces of bicycles.
we_____ our purchase contract no. 93124 in duplicate with our signature.
the buyer is satisfied with the goods, so they place another order for the same products, but the terms and conditions are different. so we can conclude it’s a/an___ order.
which of the following words are loan words?
purchase order is made by ______.
if the buyer places an order, the seller will _____ the order.
the structure of a contract includes_______.
an order is a request to supply a specified quantity of goods.
the order can be made by email but not by phone.
initial order is the same to trial order.
duplicate order means buyers are satisfied with the goods, so they place an order again with the same terms and conditions of last order.
an order should include specification and description of goods,prices involving unit price and total value,quantity and packing. but it should not include terms of payment.
it is laid down in our s/c that the covering of l/c before the end of august.
we believe we can if you agree to payment by d/p at sight.
if a letter of credit is “irrevocable”, this means that____
if the seller finds any discrepancies in the letter of credit, whom does he ask for an amendment?
the description of merchandise on the letter of credit must be identical to that on the____
the negotiable instrument includes the following except_____.
it is a written, dated and signed instrument that contains unconditional order from the drawer that directs the drawee to pay a definite sum of money to a payee on demand or at specified future date. so it’s ______.
which kind of collection is very risky for the seller?
what are the parties concerned for the remittance?
remittance can be adopted in different kinds of sales including _______.
after signing the sales contract, the importer should establish the l/c according to the contract without delay.
the phrase “observing the contract once you have signed it” is to remind the buyers of reading the contract carefully when they are signing it.
the importer dislikes messages requiring l/c extension and amendment.
the date of shipment and the validity of l/c should be extended to the same date.
the exporter insists that “5% more or less” be added to the clause of quantity because it is impossible to ship the exact amount for bulk goods.
what does a symbol of shipping mark cannot be?
what does a symbol usually contains?
packing can be ided into transport packing, inner packing and _____.
if the goods might be easily damaged through rough handling, what mark should be put in the packing?
pens are packed 10 pieces ____ a box and 200 boxes ____ a wooden case
the insurance is covered for 120% of the invoice value _____ all risks.
the insurance policy is a formal contract-document issued by an insurance company to an ____.
insurance is to be _____ by the seller on behalf of the buyer for 110% of invoice value against wpa; premium is to be for the buyer’s account.
regarding insurance, the coverage is _____ 110% of invoice value up to the port of destination only.
insurance policy is an evidence of _____ contract issued by the underwriter to the assured.
packing can be ided into transport packing (usually known as outer packing) and sales packing (usually known as packing).
conventionally, outer packing marks mainly include transport marks, directive marks and marks.
a transport mark consists of the name of the consignee or , destination and packing number.
warning marks are obvious symbols or words to warn people against the hidden of inflammables, explosives and poisonous products, e.g. “corrosives”, “explosives”, “poison”, “inflammable”, “acid with care”, etc.
special attention has been paid to the packing, which we trust will prove in every respect to your clients.
i’m afraid the cardboard boxes are not enough for transport by sea.
each set is to be put in a cardboard box, strengthened with iron straps, and then put in a wooden case. it must be strong enough to the roughest handling.
we use cardboard boxes and then them with iron straps.
do you have any specific for packing?
we trust you will give special care to the packing in order to avoid in transit.
pcs：
kg:
cbm/m3:
meas:
n.w.:
g.w.:
p/i
cust. p/o. :
b/l :
p/l :
which of the following is included in the clause of shipment?
which of the following is the most often used mode of overseas transportation?
“shipping advice” is a notice____.
if direct steamer is not available for the transportation,____.
when goods are on board a shipping vessel,____.
which of the following way of transportation is most economical?
the goods are susceptible to shock. the underlined part of the sentence means____.
if the seller sends a note to the buyer indicating the time of shipment and the time of arrival, then it’s _______.
what are the parties involved in the most movement of the goods?
shipment only refers to transportation by ships.( )
the buyer is obliged to issue all the needed shipping documents.( )
the b/l is normally made out in two sets.( )
a liner is a vessel with regular sailing or arrivals on a stated schedule between specified ports.( )
partial shipment means shipping the commodity under one contract in more than one lot.( )
it is customary to insure the goods risks of collision, leakage, pilferage, fire and storm.
the insurance is covered _____ 130% of the invoice value against all risks.
insurance ___ the goods shall be covered by us, and any extra premium for additional coverage, if required, shall be borne by the buyer.
insurance is to be effected by the seller on behalf of the buyer; premium is to be ___ the buyer's account.
important information: procedure _____ the event of loss or damage for which underwriters may be liable.
the people's insurance company of china provides three basic types: free from particular average (fpa), with particular average (wpa) and all risks.
the insured is the party who insures the other against possible losses or damage，and undertakes to make payment in cases of loss.
the policyholder is the party who is insured against possible loss and to whom payment covering the loss will be made.
special extraneous risks mean risks caused by theft, rain, leakage, shortage, breakage, dampness, mildewing (a plant disease caused by fungi), heating, taint of odor, hooking, and rusting.
basic risks coverage can be purchased independently, while the additional risks coverage cannot be purchased independently.
if one party violates or fails to carry out the contract, the other party is entitled to claim indemnity for any loss or damage. the underline part of the sentence means_____.
what is usually the first solution to a business dispute?
a “survey report” is issued by____.
the goods arrived short.the underline part of the sentence means_____.
if the goods are damaged because of rough handling during transportation, claims can be made against____.
what information should be given in a letter of claim?
our stock is exhausted.
the goods are not up to standard.the underline part of the sentence means_____.
which of the following is a direct reason for a claim?
we regret to have to lodge a complaint against you about our loss arising from your late delivery of the coffee supplies we purchased under our order no.op7836. the word underlined can be substituted for by the following:
claims are only made by the buyer against the seller.( )
any party of a contract is entitled to claim indemnity if they suffer a loss.( )
to make a complaint is always more effective than lodge a claim.( )
sometimes the shipping company should shoulder the responsibility for loss.( )
one can always claim for compensation if he/she had insured the goods before transportation.( )
a trade fair is an exhibition organized so that companies in a specific industry can ________.
what is to the overall success of a trade fair?
if you want to train your booth personnel on trade show etiquette, you may consider the following except for________.
why is proper business attire significant to business people?
what color is considered safe color in business world?
what does conservative suit mean to a lady who attends a trade fair?
if you were a male booth representative, what accessory is needed to bring to a trade exhibition?
what is the synonym for “booth”?
which of the following is considered unacceptable behavior in a trade show?
to attend a formal party, how will you dress yourself?
on formal occasions, how many colors of all your clothes should be?
on formal occasions, what kind of shoes should a man wear?
if the suit is buttoned, where should be the stickpin?
when your foreign friend says, “your new dress is so beautiful.” what are you supposed to respond?
what is the no.1 rule a lady must keep in mind when dressing for an office party?
how are you going to prepare for the upcoming job interview apart from your verbal introduction and written documentation such as your resume and application letter?
what item is not welcome to the interview office?
which of the following statements is appropriate about wearing accessories?
you’re in a restaurant and a thin soup is served in a cup with no handles. to eat it you should:
you’re at a dinner and champagne is served with the dessert. you simply can’t drink champagne yet you know the host will be offering a toast. you:
you’re at a table in a restaurant for a business dinner. midway through the meal, you’re called to the telephone. what do you do with your napkin?
you’re hosting a dinner party at a restaurant. included are two other couples, and your most valuable client and his wife. you instruct the waiter to:
you’re invited to dinner in a private home. when do you take your napkin from the table and place it on your lap? which one is not appropriate? open it immediately.
you’re scheduled to meet a business associate for working lunch and you arrive a few minutes early to find a suitable table. 30 minutes later your associate still hasn’t arrived. you:
you are at a business dinner when someone toasts you. what should you do?
when is it appropriate to take a mobile phone call during a business dinner?
at a business dinner, when can you begin talking business?
at a business dinner, when is it appropriate to have a drink?
when you use the tactic of ______ you may mean that you can get the same good products but a lower price from other supplier.
if you give another party a lowest price and stick to it, what tactic do you use?
if you want to use the tactic of caucus, what will you do during the negotiation?
if you want to persuade another party by fact, what is the best tactic?
if you use the tactic of old mother hubbard, it means that you pretend to be ______.
装船须在1月6日至1月20日之间完成（含当日）。 shipment must be made from january 6 to january 20, ___________.
新的价格表自10月1日起生效。 the new price list will become effective ______ october 1.
本合同由a公司（以下称之为“卖方”）与b公司（以下称之为“买方”）共同订立，鉴于卖方愿意依据下列规定的条款售卖下述商品，兹特立约为据，并由订约双方协议如下。 this contract is made by and between a co. (hereinafter called “the seller”) and b co. (hereinafter called “the buyer”), _______ the seller is willing to sell the buyer the commodities listed _______ on the terms and conditions stipulated below. now these presents witness that it is ________ agreed between the parties hereto as follows.
如果双方不能履行由于买方出售上述货物而承担的义务，买方因此造成的任何损失或损害，卖方均应向买方赔偿。 the seller will indemnify the buyer for any _____ arising as a result of the seller's failure to perform any of its obligation arising out of the sale of the goods to the buyer.
承包人应进行检验，并稽查建设工厂所需的一切设备，机械和材料，其中包括各种零件。contractor shall perform the ___________ of all equipment, machinery or materials including the spare parts required for the construction of the plant.
请寄有关产品的说明书，小册子或者活页目录。 we _______ if you could send us instructions, brochures, or leaflets of your products.
我方市场对微波炉的需求很大，请你们对目前能供应的型号向我方报有竞争性的价格。 there is a big demand for chinese microwave ovens. we ________ your quoting us competitive prices for models available now.
本合同签字之日3个月内，即不迟于2016年8月31日支付本合同金额的50%的预付款，计50万美元整（大写：伍拾万美圆整）。fifty percent (50%) of the total contract value as advance us $500,000 (_________) , shall be paid by party a to party b within three months, from the date of the signing of this contract, i.e. not later than august 31, 2016.
受到不可抗力事件影响的本合同规定之义务的履行时间应予延长，延长时间相等于该不可抗力事件所导致的延误时间。 the time for performing the obligations ________ specifically prevented from performance by such event of force majeure shall be extended by a period equal to the period of delay caused by such event of force majeure.
卖方须在2018年9月30日前发货。 shipment should be made by the seller _______ september 30, 2018
我方接受贵方c109号订单订购1,400件“英雄”牌男式衬衣，请按合同规定的条款开立以我方为受益人的不可撤销即期信用证，时间不晚于2019年5月5日。 we confirm having accepted your order no. c109 for 1,400 "hero" brand men’s shirts. you are kindly requested to open an irrevocable sight letter of credit in our favor __________.
若能蒙告上述公司的财务状况和可靠性，当不胜感激。 we ________ if you would furnish us with your opinion on the financial status and reliability of the above company.
若能蒙告上述公司的财务状况和可靠性，当不胜感激。 we ________ if you would furnish us with your opinion on the financial status and reliability of the above company.
随函附上报价单一份。请注意，所报价格以你方于2019年3月30日前接受为准，因其他客户对我方供应之货也有兴趣。 attached to this letter is our latest price list. we _______ to draw your attention to the fact that the price quoted by us is subject to your acceptance ________ , and the reason being that many other buyers are also interested in our suppliers.
双方在签约前交换的所有文件、书信和电子邮件，应从本合同生效之日起开始自动失效。 all documents, letters and emails interchanged between two parties ________ the signing of the contract shall become ________ automatically from the date on which the contract comes into force.
本合同由a公司（以下称之为“卖方”）与b公司（以下称之为“买方”）共同订立，鉴于卖方愿意依据下列规定的条款售卖下述商品，兹特立约为据，并由订约双方协议如下。 this contract is made by and between a co. (______ called “the seller”) and b co. (______ called “the buyer”), _______ the seller is willing to sell the buyer the commodities listed hereunder on the terms and conditions stipulated below. now these presents witness that it is ________ agreed between the parties hereto as follows.
自回归(autoregressive, ar)模型由（ ）提出 a g. e. p. box b g. m. jenkins c g. u. yule d bollerslov
哪种时间序列分析方法是从序列自相关的角度来分析（ ） a 描述性时序分析 b 频域分析 c 时域分析方法 d 谱分析
频域分析方法与时域分析方法相比（ ） a. 前者要求较强的数学基础，分析结果比较抽象，易于进行直观解释。 b. 后者要求较强的数学基础，分析结果比较抽象，不易于进行直观解释。 c. 前者理论基础扎实，操作步骤规范，分析结果易于解释。 d. 后者理论基础扎实，操作步骤规范，分析结果易于解释。
关于严平稳与（宽）平稳的关系，不正确的为( ) a. 严平稳序列不一定是宽平稳序列 b. 当序列服从正态分布时，两种平稳性等价 c. 二阶矩存在的严平稳序列一定为宽平稳的 d. 独立同分布的随机变量序列一定是宽平稳的
下列哪项属于平稳时间序列的自相关图特征？（ ） a. 自相关系数很快衰减为零 b. 自相关系数衰减为零的速度缓慢 c. 自相关系数一直为正 d. 在相关图上，呈现明显的三角对称性
利用时序图对时间序列的平稳性进行检验，下列说确的是（ ） a. 如果时序图呈现明显的递增态势，那么这个时间序列就是平稳序列。 b. 如果时序图呈现明显的周期态势，那么这个时间序列就是平稳序列。 c. 如果时序图总是围绕一个常数波动，而且其波动范围有限，那么这个时间序列是平稳序列。 d. 通过时序图不能够精确判断一个序列的平稳与否。
纯随机序列的说法，错误的是（ ） a. 纯随机序列是没有分析价值的序列 b. 纯随机序列的均值是零，方差是定值 c. 不同的时间序列平稳性检验，其延迟期数要求也不同 d. 由于观察值序列的有限性，纯随机序列的样本自相关系数不会绝对为零
对矩估计的评价，不正确的是（ ） a. 估计精度好 b. 估计思想简单直观 c. 不需要假设总体分布 d. 计算量小(低阶模型场合)
常见的时间序列分析方法包括（ ） a 描述性时序分析 b 频域分析 c 时域分析方法 d 谱分析
时域方法的特点包括 ( ) a 理论基础扎实 b 操作简单、直观有效 c 操作步骤规范 d 分析结果易于解释
下面属于自相关系数性质的是（ ） a 规范性 b 对称性 c 负定性 d 对应模型的唯一性
时间序列数据是按照时间顺序收集的一组数据。（ ）
频域分析方法是从序列自相关的角度揭示时间序列的发展规律。（ ）
特征统计量可以描述随机序列的所有统计性质。（ ）
严平稳的时间序列一定是宽平稳序列. （ ）
宽平稳正态时间序列一定是严平稳时间序列. （ ）
一个平稳时间序列一定唯一决定了它的自相关系数，反过来，一个自相关系数也唯一对应一个平稳时间序列. （ ）
平稳时间序列的自协方差函数和自相关系数只依赖于时间的平移长度而与时间的起止点无关。（ ）
白噪声序列一定是平稳序列。（ ）
对平稳时间序列模型矩估计方法评价正确的是 （ ） a 估计精度高 b 估计思想简单直观 c 不需要假设总体分布 d 计算量小
下列属于模型优化方法的有（ ） a 残差方差图定阶法 b f检验定阶法 c 最佳准则函数定阶法 d 最小二乘估计法
sbc准则有较强的一致性，但不具有有效性，而aic准则并不具有一致性，但更具有有效性。
模型平稳，则对应的满足模型的序列也平稳。
方差存在且有界的ma模型生成的序列总是平稳的。
在金融领域当中有很多冲击效应现象存在，这种现象适合用ar模型来拟合。
自相关图里拖尾的原因有可能是用样本估计总体参数时有误差。
平稳ar模型自相关系数具有截尾性，偏自相关系数具有拖尾性。
两个不同的ma模型可以具有相同的自相关图。
不可逆的ma模型的偏自相关系数也具有拖尾性。
线性最小均方误差预测是无偏的预测。
最小均方误预测误差的方差和预测步长有关，而和预测的时间原点无关。
世界上第一只晶体管是 材料的晶体管。
2000年度的诺贝尔物理学奖授予发明了世界上第一个集成电路的科学家 ，以表彰他为现代信息技术所做出的基础性贡献。
在现代集成电路制造工艺中，先进的制造工艺技术常常采用8英寸的硅片或12英寸的晶圆。其中，晶圆尺寸主要指的是硅片的 。
每立方英尺中所含直径大于0.5um颗粒数量小于1000，那么该环境的洁净等级为
所有的物品进入生产之前都必须进行清洁处理才能带入操作间。
集成电路的集成度越高，特征尺寸越小，对洁净度的要求越高。
洁净室内常见的洁净设备包括
净化设备中最核心的是过滤器。
对于洁净度高的要求利用高效过滤器，对于洁净度低的采用粗过滤器。
半导体材料主要有两大类，包括
碳化硅和氮化镓作为衬底材料常用于功率器件。
砷化镓属ⅲ－ⅴ族化合物半导体材料，易碎，需轻拿轻放。
电子迁移率比硅高6倍，多应用于超高速、超高频器件和集成电路中。
锗的禁带宽度比硅大，所制作的器件比硅耐高温。
单晶硅生长需要满足的条件包括
常见的制备单晶硅的方法有
三氯氢硅的氢还原法可以制备单晶硅。
直拉法制备的单晶直径比较大，杂质也比悬浮区熔法制备的单晶少。
剩下不多的多晶硅时，要提高温度和提拉速度，进行收尾拉光，否则容易引起坩埚的破裂。
确定单晶硅导电类型的方法是
少数载流子寿命测试方法是
常用的电阻率的测试方法是
位错是一种点缺陷，由晶胞错位引起的。
为了去除表面的杂质、缺陷，进一步去除硅片表面微量的损伤层，需要进行的工艺是
单晶硅棒形成之后，我们首先需要对其进行掐头去尾和径向研磨。
切片之前必须采用光点定向法对单晶硅进行定晶向。
一般8in以上的硅片采用内圆切割，8in以下的硅片采用线锯切割。
利用一定的刃部轮廓的砂轮磨掉硅片边缘的棱角，使之变得光滑的工艺为
双极型晶体管的制作工艺流程中，首先制备的是 ，其次制备的是 ，最后制备的是 ，依次为：
集成电路的绝缘介质隔离技术中，最常用的介质是 。
常用的电阻率的测试方法是
少数载流子寿命测试方法是
确定单晶硅导电类型的方法是
为了去除表面的杂质、缺陷，进一步去除硅片表面微量的损伤层，需要进行的工艺是
当前半导体材料 应用最广泛的是
硅片制备过程中 常常采用的定向方法是
半导体行业用到的多晶硅纯度一般为
每立方英尺中所含直径大于0.5um颗粒数量小于1000，那么该环境的洁净等级为
集成电路，按照功能可以为 。
集成电路的制造工艺，需要采用隔离技术，常见的隔离方法有 。
制备单晶硅的方法有
单晶硅生长需要满足的条件
直拉法制备单晶时，单晶炉中的电气控制系统主要控制的工艺参数有
多晶硅的制备方法有
直拉法制备硅单晶时，常常含有的杂质包括
半导体材料的特性主要包括
过滤器根据过滤效率一般可分为
直拉法制备的单晶直径比较大，杂质也比悬浮区熔法制备的单晶少。
剩下不多的多晶硅时，要提高温度和提拉速度，进行收尾拉光，否则容易引起坩埚的破裂。
三氯氢硅的氢还原法可以制备单晶硅。
位错是一种点缺陷，由晶胞错位引起的。
单晶硅棒形成之后，我们首先需要对其进行掐头去尾和径向研磨。
切片之前必须采用光点定向法对单晶硅进行定晶向。
一般8in以上的硅片采用内圆切割，8in以下的硅片采用线锯切割。
如果一个晶格原子进入间隙并产生空位，即间隙原子和空穴同时产生，这种缺陷称为弗伦克尔缺陷。
所有的物品进入生产之前都必须进行清洁处理才能带入操作间。
集成电路的集成度越高，特征尺寸越小，对洁净度的要求越高。
净化设备中最核心的是过滤器。
对于洁净度高的要求利用高效过滤器，对于洁净度低的采用粗过滤器。
硅的禁带宽度比锗大，所制作的器件比锗耐高温。
碳化硅和氮化镓作为衬底材料常用于功率器件。
砷化镓属ⅲ－ⅴ族化合物半导体材料，易碎，需轻拿轻放。
电子迁移率比硅高6倍，多应用于超高速、超高频器件和集成电路中。
特征尺寸是衡量集成电路设计和制造水平的重要尺度，它主要是指集成电路的关键尺寸，常用单位是微米和 。
利用一定的刃部轮廓的砂轮磨掉硅片边缘的棱角，使之变得光滑的工艺为
目前常见的半导体材料包括元素半导体和
单晶硅形成时，必须要有一个排列标准，这个标准称为
利用高频感应线圈对多晶硅逐段熔化，在多晶硅锭下方装置籽晶，熔区从籽晶和多晶硅锭界面开始，熔区推进，单晶拉制成功，该方法是
用于解决铝尖刺问题的方法主要有哪些？
集成电路中常常用于插塞的金属是什么？
二氧化硅的作用有哪些？
二氧化硅作为选择性扩散的条件有哪些？
金属铝互连常常出现的问题是什么？
解决铝互连电迁移问题的方法有哪些？
集成电路互连常常用难熔金属与多晶硅形成金属硅化物，常用的难熔金属有哪些？
金属薄膜在集成电路中有哪些作用？
铜作为金属互连材料有哪些缺点？
氮化硅性能比二氧化硅更加稳定，介电常数更大，因此可以得到更高的击穿电压。
多晶硅不仅可以作为栅材料，还可以作为局部互连材料，例如栅的互连。
砷化镓也是一种常见的半导体材料，属于化合物半导体，常用于制作超高速的晶体管和集成电路和各种半导体发光器件。
铝的电阻率比铜低，因此导电能力更强。
硅化钛和硅化钽常常用作金属互连工艺中的反射层和阻挡层
解决铝互连中肖特基接触的方法是在电极引出部分进行
要产生1000埃厚度的二氧化硅，需要消耗多少厚度的硅
影响热氧化速率中，哪种因素是最重要的?
增加热氧化速率的方法有哪些？
二氧化硅厚度的测试方法有哪些？
氧化层表面的缺陷有哪些？
热氧化反应一般发生在硅和二氧化硅的界面。
热氧化的速率与晶圆的晶向有关，但与氧化剂压力无关。
掺氯氧化可以减少氧化层错堆垛，吸附钠离子。
氢氧合成氧化结束时，必须将氧化炉中的氢气去除干净。
在高温条件下，硅与氧化剂反应，产生二氧化硅的工艺过程是
vpe的含义是
mocvd的含义
气相外延生长硅需要进行抛光，常用的抛光物质是
气相外延生长硅时，sicl4的浓度越高越好。
mbe的含义是
下列哪一项不符合食品安全具有的特点：
下列哪一项不符合食品安全的要求
下列哪一项不属于食品安全监督管理的原则
建立的食品召回制度是几级
下列哪一项属于食品安全重点监督管理的内容
菌落总数的食品卫生学意义之一是（ ）
大肠菌群的食品卫生学意义之一是（ ）
黄曲霉毒素的主要靶器官是
黄曲霉毒素中致癌性最强的是哪个选项？
下列食品中最易受黄曲霉毒素b1污染的是哪项？
以下关于细菌性食物中毒的流行病学特点，描述错误的是（ ）
关于沙门氏菌食物中毒，以下说确的是（ ）
关于亚硝酸盐中毒，以下说确的是（ ）
以过敏为主要症状的食物中毒是哪一类？（ ）
毒蕈中毒的临床类型中最严重的是哪一型？ （ ）
细菌性食物中毒的常见原因有什么？预防和控制细菌性食物中毒的措施有哪些？
日本水俣湾事件中造成居民健康损害的是食品中（ ）污染。
哪一类杀虫剂是我国目前使用量最大污染最为广泛的农药？（ ）
“痛痛病”事件中造成居民健康损害的是食品中（ ）污染。
拟除虫菊酯类农药的毒性机制为：（ ）
急性中毒后可能会发生迟发性神经毒性作用的是哪一类农药？（ ）
（1）食品中有毒金属的污染来源（途径）有哪些？ （2）如何控制有毒金属的污染及危害？
级数
求的和。
级数和级数有相同的敛散性。
如果级数均发散，则级数发散。
判断级数 的敛散性。
如果级数都收敛，那么级数也收敛。
判断级数的敛散性
如果级数收敛，而且对于任意的也收敛。
级数收敛。
级数发散。
级数收敛。
对于收敛的正项级数，其通项必定单调趋于零。
级数发散。
判别级数的敛散性
判别级数的敛散性。
判别级数，的敛散性。
级数收敛。
级数收敛。
级数收敛.
判别级数的敛散性。
求级数的和。
求级数的和。
关于级数，下列叙述正确的是（）
级数收敛。
判别级数收敛。
判断级数的敛散性。
如果正项级数收敛，级数发散，那么除去有限项外，必定有.
对于任意收敛的正项级数，总是存在常数使得除去有限项外，满足
如果正项级数满足，则该级数收敛。
判别级数的敛散性。
判别级数的敛散性。
判别级数的敛散性。
判别级数的敛散性。
判别级数的敛散性。
判别级数敛散性。
关于级数，下列说确的是（）
如果正项级数收敛，那么级数也收敛。
级数和正项级数有相同的敛散性。
判断正项级数的敛散性。
判断正项级数的敛散性。
级数条件收敛。
级数条件收敛。
级数条件收敛
级数条件收敛
级数绝对收敛
如果级数绝对收敛，那么级数绝对收敛。
关于级数，下列叙述正确的有（）
如果正项级数收敛，而且数列单调，那么级数收敛。
判别级数的敛散性
判别级数的敛散性
对于收敛的正项级数，其通项必定单调趋于零。
判断级数的收敛性。
函数列的收敛域是实数域。
函数列的收敛域是实数域。
函数列的一致收敛域为（）
函数列在(-1,1)上一致收敛
函数列在实数域上内闭一致收敛。
函数列在[0, 1)上一致收敛
函数列在[0, 1]上一致收敛
关于函数项级数，下列叙述正确的有（）
在[0,1]上定义函数列，则下列叙述正确的有（）
函数项级数在[0, 1]上一致收敛
函数项级数在[-1,1]上一致收敛
函数项级数在[0, 1]上一致收敛
函数项级数在实数域上不一致收敛
函数项级数在实数域上一致收敛
函数列一致收敛。
函数列一致收敛。
关于函数列，下列叙述正确的有（ ）
关于函数列，下列叙述正确的有（ ）
如果函数列在区间i上连续，的极限函数连续，那么一定一致收敛到
如果函数列在（0, 1）上内闭一致收敛于函数，那么
的和函数为那么（ ）
设( )
求极限=（ ）
设（）
关于函数叙述正确的有（ ）
关于函数项级数，正确的有（ ）
关于幂级数的收敛域，正确的是（ ）
幂级数的收敛域是（）
关于幂级数，正确的有（ ）
幂级数的收敛域为（）
幂级数的收敛域为（）
幂级数的收敛域为（）
关于幂级数，下列说确的有（ ）
假设幂级数的收敛域分别为，则下列说确的是（）
幂级数的收敛半径为（）
和有相同的收敛域。
假设为关于x的奇函数，那么
幂级数的收敛域为（）
假设数列为等差数列，那么幂级数的收敛半径是（）
关于幂级数，正确的叙述有（ ）
关于幂级数，叙述正确的有（）
，其中b>a>0.
幂级数的收敛域是（ ）
关于幂级数，叙述正确的有（）
关于幂级数，叙述正确的有（ ）
幂级数的收敛域是（-2， 4）。
的收敛域为
的收敛域是[-1, 1).
函数的麦克劳林展开式是( )
函数的麦克劳林展开式为（）
多项式在处的泰勒展开式为( )
函数的麦克劳林展开示为（ ）
的麦克劳林展开式为（ ）
函数的麦克劳林展开式为（ ）
函数的麦克劳林展开式为（ ）
在处的展开式为（ ）
的麦克劳林展开式为（ ）
的麦克劳林展开式为（）
的展开式为（ ）
函数按照的幂次展开的级数为（）
函数的麦克劳林展开式为（ ）
函数的麦克劳林展开式为（ ）
的值为（ ）
的值为（ ）
利用幂级数展开式求 =( )
函数在处的泰勒展开式为
函数的幂级数站开始为
函数在x=0处的幂级数展开式为
函数在上展开成余弦级数为（ ）
函数在的正弦级数展开式为（ ）
函数在[0， 4]上的余弦级数展开式为（ ）
函数在(0, 1)上的余弦级数为
可以将展开成
可以将函数展开成
每一个三角级数一定是某个可积的周期函数的傅里叶级数。
假设函数是上的可积函数，如果的傅立叶级数在上一致收敛于，那么
设是以为周期的函数，则其傅里叶级数是（）
设是以为周期的函数，则关于该函数的傅里叶系数，下列说确的有（ ）
设是以为周期的函数，则关于该函数的傅里叶系数，下列说确的有（ ）
设是以为周期的函数，则的傅里叶级数在处的值为（）
设函数满足，那么该函数的傅里叶级数中只出现奇次项。
设函数满足，那么该函数的傅里叶级数中只出现奇次项。
函数的傅里叶级数是（）
函数的傅里叶级数为（）
函数的傅里叶级数为（）
函数的傅里叶级数是（ ）
可以根据函数的傅里叶级数得到
函数的傅里叶级数为（）
函数的傅里叶级数为（ ）
函数的傅里叶级数是
是上的正交函数系。
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