• Title/Summary/Keyword: C.T.R.

Search Result 3,345, Processing Time 0.034 seconds

이소니트릴의 자유라디칼반응 (Homolytic Reactions of Isonitriles)

  • 김성수
    • 대한화학회지
    • /
    • 제24권3호
    • /
    • pp.250-258
    • /
    • 1980
  • 여러종류의 자유라디칼들이 이소니트릴에 첨가되어 중간체인 imidoyl 자유라디칼 RN=CR'을 형성한다. 이것은 또한 imine으로부터 imidoyl hydrogen 을 떼어 내는 다음과 같은 반응에 의해서도 생성될 수 있다. RN=C(H)R' + R"${\cdot}{\rightarrow}$ RN=CR' + R"-H 중간체인 imidoyl 자유라디칼은 ${\beta}$-cleavage 및 aton transfer 반응을 통해서 안정된 분자를 형성한다. ${\beta}$-cleavage는 imidoyl 자유라디칼의 구조에 따라서 두개의 다른 방향으로의 반응이 가능하다. Cyanide transfer와 소위 말하는 정상적인 ${\beta}$-cleavage가 그러한 반응들이다. t-Butoxy 자유라디칼이 t-butylisonitrile 7에 첨가되면 중간체인 t-Bu-N=C-O-Bu-t가 생성되는데, 이것은 ${\beta}$-cleavage반응을 통해서 t-butylisocyanate와 t-butyl 자유라디칼을 형성한다. Phenyl 자유라디칼은 7에 첨가되어 중간체인 t-Bu-N=$C-C_6H_5$를 형성하는데 이것은 cyanide transfer 반응을 통해서 benzonitrile과 t-butyl 자유라디칼로 분해된다. 여기서 생성되는 t-butyl 자유라디칼은 다시 7에 첨가하여 intermediate인 자유라디칼 t-Bu-N=C-Bu-t을 형성하고, 이것은 다시 pivalonlonitrile과 t-butyl 자유라디칼로 분해되는데 이러한 반응이 반복되므로 radical chain isomerization을 일으킨다. Silyl 자유라디칼은 7에 첨가되어 t-Bu-N=$C-Si(CH_3)_3$를 형성하고, 이것은 cyanide transfer 반응을 거쳐서 다시 $(CH_3)_3$SiCN과 t-butyl 자유라디칼로 분해된다.

  • PDF

자극방법별 바윗굴, Crassostrea nippona 의산란효과와 난발생 및 유생사육에 미치는 수온의 영향 (Spawning induction accrding to Stimulating Treatment and Influence of Water Temperature on Egg Development and Larvae Rearing of Oyster , Crassostrea nippona)

  • 유성규;강경호
    • 한국패류학회지
    • /
    • 제12권2호
    • /
    • pp.91-97
    • /
    • 1996
  • 바윗굴의 산란유발 및 종묘생산을 위한 생물학적 기초자료를 얻고자 자극방법별 효과와 난발생 및 유생사육에 미치는 수온의 영향에 관하여 실험한 결과, 자극방법별 산란유발은 정자현탁액 첨가구에서 가장 많은 산란량과 높은 수정률을 나타냈고, 난발생 및 유생사육의 각 단계에 이르기까지의 수온(T, $^{\circ}C$)에 따른 발생속도(h, 시간)는 수온이 높을 수록 빨랐으며, 그 관계식은 다음과 같다. 담륜자기 :1/h= 0.0069T - 0.0950(r=0.9447)D형 유생 :1/h= 0.0006T - 0.0045(r=0.9288)초기 각정기 유생:1/h= 0.0002T - 0.0019(r=0.9358)후기 각정기 유생:1/h= 0.0002T - 0.0022(r=0.9868)부착기 유생:1/h= 0.0001T - 0.0013(r=0.9897)또한 바윗굴의 수온과 난발생 속도와의 관계에서 추정된 난발생의 생물학적 영도는 평균 10.96$^{\circ}C$였으며, 수온별 유생사육시 바윗굴의 생존율은 24$^{\circ}C$에서 6.8%로 가장 좋았다.

  • PDF

On Approximation of Functions Belonging to Lip(α, r) Class and to Weighted W(Lr,ξ(t)) Class by Product Mean

  • Nigam, Hare Krishna;Sharm, Ajay
    • Kyungpook Mathematical Journal
    • /
    • 제50권4호
    • /
    • pp.545-556
    • /
    • 2010
  • A good amount of work has been done on degree of approximation of functions belonging to Lip${\alpha}$, Lip($\xi$(t),r) and W($L_r,\xi(t)$) and classes using Ces$\`{a}$ro, N$\"{o}$rlund and generalised N$\"{o}$rlund single summability methods by a number of researchers ([1], [10], [8], [6], [7], [2], [3], [4], [9]). But till now, nothing seems to have been done so far to obtain the degree of approximation of functions using (N,$p_n$)(C, 1) product summability method. Therefore the purpose of present paper is to establish two quite new theorems on degree of approximation of function $f\;\in\;Lip({\alpha},r)$ class and $f\;\in\;W(L_r,\;\xi(t))$ class by (N, $p_n$)(C, 1) product summability means of its Fourier series.

A TIME-INDEPENDENT CONDITIONAL FOURIER-FEYNMAN TRANSFORM AND CONVOLUTION PRODUCT ON AN ANALOGUE OF WIENER SPACE

  • Cho, Dong Hyun
    • 호남수학학술지
    • /
    • 제35권2호
    • /
    • pp.179-200
    • /
    • 2013
  • Let $C[0,t]$ denote the function space of all real-valued continuous paths on $[0,t]$. Define $X_n:C[0,t]{\rightarrow}\mathbb{R}^{n+1}$ by $Xn(x)=(x(t_0),x(t_1),{\cdots},x(t_n))$, where $0=t_0$ < $t_1$ < ${\cdots}$ < $t_n$ < $t$ is a partition of $[0,t]$. In the present paper, using a simple formula for the conditional expectation given the conditioning function $X_n$, we evaluate the $L_p(1{\leq}p{\leq}{\infty})$-analytic conditional Fourier-Feynman transform and the conditional convolution product of the cylinder functions which have the form $$f((v_1,x),{\cdots},(v_r,x))\;for\;x{\in}C[0,t]$$, where {$v_1,{\cdots},v_r$} is an orthonormal subset of $L_2[0,t]$ and $f{\in}L_p(\mathbb{R}^r)$. We then investigate several relationships between the conditional Fourier-Feynman transform and the conditional convolution product of the cylinder functions.

CONVERGENCE OF APPROXIMATING FIXED POINTS FOR NONEXPANSIVE NONSELF-MAPPINGS IN BANACH SPACES

  • Jung, Jong-Soo;Park, Jong-Seo;Park, Eun-Hee
    • 대한수학회논문집
    • /
    • 제12권2호
    • /
    • pp.275-285
    • /
    • 1997
  • Let E be a uniformly convex Banach space with a uniformly G$\hat{a}teaux differentiable norm, C a nonempty closed convex subset of $E, T : C \to E$ a nonexpansive mapping, and Q a sunny nonexpansive retraction of E onto C. For $u \in C$ and $t \in (0,1)$, let $x_t$ be a unique fixed point of a contraction $R_t : C \to C$, defined by $R_tx = Q(tTx + (1-t)u), x \in C$. It is proved that if ${x_t}$ is bounded, then the strong $lim_{t\to1}x_t$ exists and belongs to the fixed point set of T. Furthermore, the strong convergence of ${x_t}$ in a reflexive and strictly convex Banach space with a uniformly G$\hat{a}$teaux differentiable norm is also given in case that the fixed point set of T is nonempty.

  • PDF

CHANGE OF SCALE FORMULAS FOR A GENERALIZED CONDITIONAL WIENER INTEGRAL

  • Cho, Dong Hyun;Yoo, Il
    • 대한수학회보
    • /
    • 제53권5호
    • /
    • pp.1531-1548
    • /
    • 2016
  • Let C[0, t] denote the space of real-valued continuous functions on [0, t] and define a random vector $Z_n:C[0,t]{\rightarrow}\mathbb{R}^n$ by $Z_n(x)=(\int_{0}^{t_1}h(s)dx(s),{\ldots},\int_{0}^{t_n}h(s)dx(s))$, where 0 < $t_1$ < ${\cdots}$ < $ t_n=t$ is a partition of [0, t] and $h{\in}L_2[0,t]$ with $h{\neq}0$ a.e. Using a simple formula for a conditional expectation on C[0, t] with $Z_n$, we evaluate a generalized analytic conditional Wiener integral of the function $G_r(x)=F(x){\Psi}(\int_{0}^{t}v_1(s)dx(s),{\ldots},\int_{0}^{t}v_r(s)dx(s))$ for F in a Banach algebra and for ${\Psi}=f+{\phi}$ which need not be bounded or continuous, where $f{\in}L_p(\mathbb{R}^r)(1{\leq}p{\leq}{\infty})$, {$v_1,{\ldots},v_r$} is an orthonormal subset of $L_2[0,t]$ and ${\phi}$ is the Fourier transform of a measure of bounded variation over $\mathbb{R}^r$. Finally we establish various change of scale transformations for the generalized analytic conditional Wiener integrals of $G_r$ with the conditioning function $Z_n$.

NEHARI MANIFOLD AND MULTIPLICITY RESULTS FOR A CLASS OF FRACTIONAL BOUNDARY VALUE PROBLEMS WITH p-LAPLACIAN

  • Ghanmi, Abdeljabbar;Zhang, Ziheng
    • 대한수학회보
    • /
    • 제56권5호
    • /
    • pp.1297-1314
    • /
    • 2019
  • In this work, we investigate the following fractional boundary value problems $$\{_tD^{\alpha}_T({\mid}_0D^{\alpha}_t(u(t)){\mid}^{p-2}_0D^{\alpha}_tu(t))\\={\nabla}W(t,u(t))+{\lambda}g(t){\mid}u(t){\mid}^{q-2}u(t),\;t{\in}(0,T),\\u(0)=u(T)=0,$$ where ${\nabla}W(t,u)$ is the gradient of W(t, u) at u and $W{\in}C([0,T]{\times}{\mathbb{R}}^n,{\mathbb{R}})$ is homogeneous of degree r, ${\lambda}$ is a positive parameter, $g{\in}C([0,T])$, 1 < r < p < q and ${\frac{1}{p}}<{\alpha}<1$. Using the Fibering map and Nehari manifold, for some positive constant ${\lambda}_0$ such that $0<{\lambda}<{\lambda}_0$, we prove the existence of at least two non-trivial solutions

ITERATIVE METHODS FOR LARGE-SCALE CONVEX QUADRATIC AND CONCAVE PROGRAMS

  • Oh, Se-Young
    • 대한수학회논문집
    • /
    • 제9권3호
    • /
    • pp.753-765
    • /
    • 1994
  • The linearly constrained quadratic programming(QP) considered is : $$ min f(x) = c^T x + \frac{1}{2}x^T Hx $$ $$ (1) subject to A^T x \geq b,$$ where $c,x \in R^n, b \in R^m, H \in R^{n \times n)}$, symmetric, and $A \in R^{n \times n}$. If there are bounds on x, these are included in the matrix $A^T$. The Hessian matrix H may be positive definite or negative semi-difinite. For large problems H and the constraint matrix A are assumed to be sparse.

  • PDF